The Posse Comitatus Act and Related Matters: The Use of the Military to Execute Civilian Law

The Posse Comitatus Act and Related Matters:

The Use of the Military to Execute

Civilian Law

,name redacted,

Legislative Attorney

Updated November 6, 2018

Congressional Research Service

7-....

www.crs.gov

R42659

The Posse Comitatus Act and Related Matters

Summary

The Constitution permits Congress to authorize the use of the militia “to execute the Laws of the

Union, suppress Insurrections and repel Invasions.” And it guarantees the states protection against

invasion or usurpation of their “republican form of government,” and, upon the request of the

state legislature, against “domestic violence.” These constitutional provisions are reflected in the

Insurrection Acts, which have been invoked numerous times both before and after passage of the

Posse Comitatus Act, 18 U.S.C. Section 1385, in 1878. Congress has also enacted a number of

statutes that authorize the use of land and naval forces to execute their objective.

The Posse Comitatus Act outlaws the willful use of any part of the Army or Air Force to execute

the law unless expressly authorized by the Constitution or an act of Congress. History supplies

the grist for an argument that the Constitution prohibits military involvement in civilian affairs

subject to only limited alterations by Congress or the President, but the courts do not appear to

have ever accepted the argument unless violation of more explicit constitutional command could

also be shown. The express statutory exceptions include the legislation that allows the President

to use military force to suppress insurrection or to enforce federal authority, 10 U.S.C. Sections

251-255, and laws that permit the Department of Defense to provide federal, state and local

police with information, equipment, and personnel, 10 U.S.C. §§ 271-284.

Case law indicates that “execution of the law” in violation of the Posse Comitatus Act occurs (a)

when the Armed Forces perform tasks assigned to an organ of civil government, or (b) when the

Armed Forces perform tasks assigned to them solely for purposes of civilian government.

Questions concerning the act’s application arise most often in the context of assistance to civilian

police. At least in this context, the courts have held that, absent a recognized exception, the Posse

Comitatus Act is violated when (1) civilian law enforcement officials make “direct active use” of

military investigators; or (2) the use of the military “pervades the activities” of the civilian

officials; or (3) the military is used so as to subject “citizens to the exercise of military power

which was regulatory, prescriptive, or compulsory in nature.” The act is not violated when the

Armed Forces conduct activities for a military purpose.

The language of the act mentions only the Army and the Air Force, but it is applicable to the

Navy and Marines by virtue of administrative action and commands of other laws. The law

enforcement functions of the Coast Guard have been expressly authorized by act of Congress and

consequently cannot be said to be contrary to the act. The act has been applied to the National

Guard when it is in federal service, to civilian employees of the Armed Forces, and to off-duty

military personnel. The act probably only applies within the geographical confines of the United

States, but supplemental provisions of 10 U.S.C. §§ 271-284 appear to apply worldwide.

Finally, the act is a criminal statute under which there has been but a handful of known

prosecutions. Although violations will on rare occasions result in the exclusion of evidence, the

dismissal of criminal charges, or a civil cause of action, as a practical matter compliance is

ordinarily the result of military self-restraint.

This report provides an historical analysis of the use of the Armed Forces to execute domestic law

and of the Posse Comitatus Act, including their apparent theoretical and constitutional

underpinnings. The report then outlines the current application of the act as well as its statutory

exceptions, and reviews the consequences of its violation. This report appears in abridged form as

CRS Report R42669, The Posse Comitatus Act and Related Matters: A Sketch.

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The Posse Comitatus Act and Related Matters

Contents

Introduction ..................................................................................................................................... 1

Background ..................................................................................................................................... 2

The Use of Federal Troops Prior to 1878 ........................................................................................ 5

The Insurrection Act and Other Statutes ................................................................................... 7

Resistance to Taxes and Duties ........................................................................................... 9

Neutrality Act Enforcement .............................................................................................. 10

Requests from States for Military Aid ............................................................................... 11

Trouble in the Western States and Territories ................................................................... 15

Slavery, the Civil War, and Reconstruction ...................................................................... 16

Use of Military Forces as a Posse Comitatus .......................................................................... 17

Passage of the Posse Comitatus Act .............................................................................................. 21

Constitutional Considerations ....................................................................................................... 23

Constitutional Origins ............................................................................................................. 23

Presidential vs. Congressional Powers .................................................................................... 26

Constitutional Exceptions ....................................................................................................... 28

When the Posse Comitatus Act Does Not Apply ........................................................................... 30

Statutory Exceptions ............................................................................................................... 31

Generally........................................................................................................................... 31

The Insurrection Acts ........................................................................................................ 34

Support to Law Enforcement ............................................................................................ 42

Military Purpose ...................................................................................................................... 49

Coverage of the Posse Comitatus Act ........................................................................................... 55

Willful Use .............................................................................................................................. 55

Execute the Law ...................................................................................................................... 56

Military Coverage ................................................................................................................... 59

Navy & Marines................................................................................................................ 59

Coast Guard ...................................................................................................................... 60

National Guard .................................................................................................................. 61

Off Duty Military, Acting as Citizens & Civilian Employees........................................... 62

Geographical Application........................................................................................................ 64

Consequences of Violation ............................................................................................................ 66

Prosecution .............................................................................................................................. 66

Exclusion of Evidence............................................................................................................. 66

Jurisdiction & Criminal Defenses ........................................................................................... 68

Civil Liability .......................................................................................................................... 69

Compliance.................................................................................................................................... 70

Contacts

Author Contact Information .......................................................................................................... 70

Acknowledgments ......................................................................................................................... 70

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The Posse Comitatus Act and Related Matters

Whoever, except in cases and under circumstances expressly authorized by the

Constitution or Act of Congress, willfully uses any part of the Army or the Air Force as a

posse comitatus or otherwise to execute the laws shall be fined under this title or

imprisoned not more than two years, or both. 18 U.S.C. § 1385.

Introduction

Americans have a tradition, born in England and developed in the early years of our nation, that

abhors military involvement in civilian affairs, at least under ordinary circumstances. It finds its

most tangible expression in the 19th century Posse Comitatus Act, 18 U.S.C. Section 1385, which

forbids use of the Army and (as amended) the Air Force to execute civil law except where

expressly authorized.

The exception documents a contrary component of the tradition. Congress has expressly approved

the use of the Armed Forces in extraordinary circumstances or where federal manpower to

enforce the law was seen as inadequate. Striking the balance between rule and exception has

never been easy, but failure to do so has often proven unfortunate. If the rule is too unforgiving, a

Shays’s Rebellion may go unchecked. If exceptions are too generously granted, a Boston

Massacre or Kent State tragedy may follow.

The terrorist attacks against the United States in September 2001 produced some calls for more

generous exceptions to the rule.1 The USA PATRIOT Act2 broadened the permissible

circumstances for the use of the military to assist law enforcement agencies in countering

terrorism,3 but Congress also reaffirmed its determination to maintain the principle of the posse

comitatus law.4 The perceived breakdown in civil law and order in Hurricane Katrina’s wake

evoked more calls to reevaluate the military’s role in responding to disasters.5 The possibility of

using military surveillance equipment and resources, including unmanned aerial vehicles

(drones), to assist civilian law enforcement has raised some objections based on the military role.6

This report provides an historical analysis of the use of the Armed Forces to execute domestic law

and of the Posse Comitatus Act, including their apparent theoretical and constitutional

underpinnings. The report then outlines the current application of the Posse Comitatus Act as well

as its statutory exceptions, and reviews the consequences of its violation.

1 See Nathan Canestaro, Homeland Defense: Another Nail in the Coffin for Posse Comitatus, 12 WASH. U. J.L. & POL’Y

99, 100 (2003) (“Some politicians and media sources now suggest that Congress amend or even repeal the PCA to

allow a degree of domestic military involvement that would have been unthinkable five years ago.”). For a review of

the changed role of the military, see William C. Banks, The Normalization of Homeland Security after September 11:

The Role of the Military in Counterterrorism Preparedness and Response, 64 LA. L. REV. 745 (2004).

2 P.L. 107-56, 115 Stat. 272 (2001).

3 Id. § 104 (amending 18 U.S.C. § 2332e).

4 Homeland Security Act of 2002, P.L. 107-296, § 886, 116 Stat. 2248 (2002), codified at 6 U.S.C. § 466 (2018).

5 See Lisa Grow Sun, Disaster Mythology and the Law, 96 CORNELL L. REV. 1131 (2011); Jerald A. Sharum, The

Politics of Fear and Outsourcing Emergency Powers: The Death and Rebirth of the Posse Comitatus Act, 37 LINCOLN

L. REV. 111 (2009-2010);, William C. Banks, Providing “Supplemental Security”—The Insurrection Act and the

Military Role in Responding to Domestic Crises, 3 J. NAT'L SECURITY L. & POL'Y 39 (2009) (all three articles

recounting history behind the short-lived amendment to the Insurrection Act enacted in response to Hurricane Katrina).

6 Canestaro, supra, note 1, at 100 (arguing that numerous exceptions for military support of civil authorities “have

taken their toll on the [Posse Comitatus Act’s] strength”).

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Background

The Magna Carta provides the first recorded acknowledgment of the origins of the AngloAmerican tradition against military involvement in civilian affairs with its declaration that “no

free man shall be ... imprisoned ... or in any other way destroyed ... except by the legal judgment

of his peers or by the law of the land.”7 Subsequent legislation in the reign of Edward III

explained that this precluded punishment by the King except “in due Manner ... or by Process

made by Writ ... [or] by Course of the Law,”8 or as later more simply stated, except “by due

Process of the Law.”9 Three hundred years after the passage of the Edwardian statutes, Lord Coke

and other members of Parliament read these due process and law of the land requirements to

include a broad prohibition against the use of martial law in peacetime, an interpretation they

compelled King Charles I to acknowledge.10

King Charles I, preparing for a military expedition in France, had quartered his troops in homes

along the southern English coastline.11 Rioting resulted, and the participants, both military and

civilian, were tried and punished by commissioners operating under the authority of martial law.

Offended by this peacetime exercise of military judicial authority over civilians, Parliament

sought and was granted the Petition of Right of 1628, which outlawed both quartering and martial

law commissions.12

7 Magna Carta, ch. 39 (1225)[ch.29 in the Charter of King John (1215)], reprinted in WILLIAM F. SWINDLER, MAGNA

CARTA: LEGEND AND LEGACY 315-16 (1965) (“No freeman shall be taken, or imprisoned, or be disseised of any

freehold, or liberties, or free customs, or outlawed, or banished, or in any other way destroyed, nor will we go or send

against him, except by the lawful judgment of his peers or by the law of the land”) (language added to ch.29 of the

Charter of King John in the reissuance by King Henry III appears in italics). Although the Magna Carta in the modified

version of King Henry III remains in effect, the language quoted above is generally cited as “chapter 29.” See, e.g.,

FAITH THOMPSON, MAGNA CARTA: ITS ROLE IN THE MAKING OF THE ENGLISH CONSTITUTION 1300-1629, at 68 (1948);

SIR MATTHEW HALE, THE HISTORY OF THE COMMON LAW OF ENGLAND 49 (1716 ed.); 1 SIR EDWARD COKE, THE SECOND

PART OF THE INSTITUTES OF THE LAWS OF ENGLAND 45 (1797 ed.); I SIR WILLIAM BLACKSTONE, COMMENTARIES ON THE

LAWS OF ENGLAND 400 (1765 ed.).

8 25 Ed. III. Stat. 5, ch. 4 (1352), reprinted in 1 STATUTES OF THE REALM, 1231-1377 321 (1993):

Whereas it is contained in the Great Charter of the Franchises of England, that none shall be

imprisoned nor put out of his Freehold, nor of his Franchises nor free Custom, unless it be by the

Law of the Land; It is accorded assented, and established, That from henceforth none shall be taken

by Petition or Suggestion made to our Lord the King, or to his Council, unless it be by Indictment

or Presentment of good and lawful People of the same neighbourhood where such Deeds be done,

in due Manner, or by Process made by Writ original at the Common Law; nor that none be out of

his Franchises, nor of his freeholds, unless he be duly brought into answer, and forejudged of the

same by the Course of the Law; and if any thing be done against the same, it shall be redressed and

holden for none.

9 28 Ed. III. chs. 1, 3 (1354), reprinted in 1 STATUTES OF THE REALM, 1231-1377 at 345 (1993) (“the Great Charter ...

[shall] be kept and maintained in all Points.... No Man of what[ever] Estate or Condition that he be, shall be put out of

land or Tenement, nor taken, nor imprisoned, nor disinherited, nor put to Death, without being brought in Answer by

due Process of the Law.”).

10 See THOMPSON, supra note 7, at 347-50; David E. Engdahl, Soldiers, Riots, and Revolution: The Law and History of

Military Troops in Civil Disorders, 57 IOWA L. REV.1, 10-11 (1971). Coke’s Institutes make the same point;

proceedings under martial law are not proceedings under the “law of the land” (lex terrae). See I COKE, supra note 7, at

50 (“And so if two English men doe goe into a foreine kingdome, and fight there, and the one murder the other, lex

terrae extendeth not hereunto, but this offense shall be heard, and determined before the constable, and marshall [i.e. at

martial law], and such proceedings shall be there, by attaching of the body, and otherwise, as the law, and custom of

that court have been allowed by the lawes of the realme, [13 H.IV. ch.5 (1412)]”).

11 For a more expansive examination, see Engdahl, supra note 10, at 22-23.

12 Restating the relevant guarantees of the Magna Carta and subsequent statutes, Parliament declared:

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When, in the following century, the British responded to colonial unrest by quartering troops in

Boston, the colonists saw it as a breach of this fundamental promise of English law.13 Their

circumstances, however, were not exactly identical to those surrounding the Petition of Right.

First, the question arose in the British colonies rather than England itself. England had stationed

troops in the colonies to protect them against the French and Indians and had opted for military

governorships in other territories.14 Second, there was no military usurpation of judicial functions.

The colonists remained subject to civil rather than military justice,15 and soldiers who employed

[N]everthess of late time divers commissions under your Majesty’s great seal have issued forth, by

which certain persons have been assigned and appointed commissioners with power and authority

to proceed within the land, according to the justice of martial law, against such soldiers or mariners,

or other dissolute persons joining with them, as should commit any murder, robbery, felony,

mutiny, or other outrage or misdemeanour whatsoever, and by such summary course and order as is

agreeable to martial law, and as is used in armies in time of war, to proceed to the trial and

condemnation of such offenders, and them to cause to be executed and put to death according to the

law martial.... They do therefore humbly pray your most excellent Majesty ... that your Majesty

would be pleased to remove the said soldiers and mariners, and that your people may not be so

burdened in time to come; and that the aforesaid commissions, for proceeding by martial law, may

be revoked and annulled; and that hereafter no commissions of like nature may issue forth to any

person or persons whatsoever to be executed as aforesaid, lest by colour of them any of your

Majesty’s subjects be destroyed or put to death contrary to the laws and franchise of the land.

Petition of Right, 3 Car. I, c.1, §§ 3, 4, 7, 10, reprinted in WILLIAM STUBBS, SELECT CHARTERS AND OTHER

ILLUSTRATIONS OF ENGLISH CONSTITUTIONAL HISTORY FROM THE EARLIEST TIMES TO THE REIGN OF EDWARD THE FIRST

515-17 (8th ed. 1895); and 5 STATUTES OF THE REALM 23, 24 (1993).

The Petition of Right was understood to have established, with respect to martial law,

First, That in truth and reality it is not a law, but something indulged rather than allowed as a law;

the necessity of government, order and discipline in an army, is that only which can give those laws

a countenance. Secondly, This indulged law was only to extend to members of the army, or to those

of the opposite army, and never was so much indulged as intended to be (executed or) exercised

upon others; for others were not listed under the army, had no colour of reason to be bound by

military constitutions, applicable only to the army; whereof they were not parts, but they were to be

ordered and governed according to the laws to which they were subject, though it were a time of

war. Thirdly, That the exercise of martial law, whereby any person should lose his life or member,

or liberty, may not be permitted in time of peace, when the King’s courts are open for all persons to

receive justice, according to the laws of the land.

HALE, supra note 7, at 39-40.

According to Blackstone,

the necessity of order and discipline in an army is the only thing which can give ... countenance [to

martial law]; and therefore it ought not to be permitted in time of peace, when the king’s courts are

open for all persons to receive justice according to the laws of the land.... And it is laid down, that

if a lieutenant, or other, that hath commission of martial authority, doth in time of peace hang or

otherwise execute any one by colour of martial law, this is murder; for it is against the magna carta.

And the petition of right enacts, that no soldier shall be quartered on the subject without his own

consent; and that no commission shall issue to proceed within this land according to martial law.

And whereas, after the restoration, king Charles the second kept up about five thousand regular

troops, by his own authority, for guards and garrisons; which king James the second by degrees

increased to no less than thirty thousand, all paid from his own civil list; it was made one of the

articles of the bill of rights, that the raising or keeping of a standing army within the kingdom in

time of peace, unless it be with the consent of the parliament, is against the law.

I BLACKSTONE, supra note 7, at 400.

13 Engdahl, supra note 10, at 22.

14 Id. at 23 (explaining that Canada was governed by military rule from 1760-1763).

15 Id. at 24 (noting that Parliament had rejected military commissions to try civilians for offenses).

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more force than civilian law permitted were themselves subject to civilian justice as the trial of

the soldiers involved in the Boston Massacre demonstrates.16

On the other hand, the troops involved in the Boston Massacre were stationed in Massachusetts

not for protection against a marauding invader as they had been in the French and Indian Wars,

nor to accomplish the transition between civil governments within a conquered territory as they

had been after the French lost Canada to the British as a consequence of those conflicts, but as an

independent military force quartered among a disgruntled civilian population to police it.17 Public

resentment of the use of the troops in such a manner sparked the incident, which led in turn to

further heightened resentment.18

In any event, the experience was sufficiently vexing that the Declaration of Independence listed

among our grievances against Great Britain that the King had “kept among us, in times of peace,

Standing Armies without the consent of our legislatures,” had “affected to render the Military

independent of and superior to the civil power,” and had “quarter[ed] large bodies of armed

troops among us ... protecting them, by a mock trial, from punishment for any murders which

they should commit on the inhabitants of these States.”19

The Articles of Confederation for the newly established United States addressed the threat of

military intrusion into civilian affairs by demanding that the Armed Forces assembled during

peacetime be no more numerous than absolutely necessary for the common defense; by entrusting

control to civil authorities within the states; and by a preference for the farmer in arms as a

member of the militia over the standing professional army.20

16 Id. at 25.

17 HILLER B. ZOBEL, THE BOSTON MASSACRE 135 (1987) (“The soldiers, one ought always to remember, went into

Boston not as an occupying army but rather as a force of uniformed peace-keepers, or policemen. Their role as even the

radicals conceived it was to assist the executive and if necessary the courts to maintain order.”).

18

See Engdahl, supra note 10, at 24-25:

The last die was cast when two regiments of troops were quartered in Boston at the end of the

decade. Boston was a hotbed of colonial discontent. The assemblage of military troops for control

of possible disorders aggravated the discontent, not only because it affronted the English tradition

against domestic use of military troops, but also because it was without warrant in the charter of

Massachusetts Bay. The unwelcome troops were frequently taunted and vilified, and the ultimate

and inevitable outrage soon occurred…. A crowd of angry Bostonians ... blocked the path of a

detachment of soldiers marching to their post. The soldiers made ready to force their passage, but

were ordered back to the main guard.... The crowd approached the main guard with angry and

opprobrious taunts. A sentinel struck one particularly bothersome boy with the butt of his musket,

and quickly a crowd converged on that spot throwing snowballs and rocks at the sentinel along with

verbal threats on his life. The sentinel loaded his musket and waved it at the mob, a squad of

soldiers were sent to his aid. The soldiers, soon joined by a colonel, loaded their muskets as the

crowd hooted and jeered and berated them and dared them to shoot. They kept the crowd back a

time with bayonets, but then suddenly fired. It was never made clear – it never is – whether they

had fired on their officer’s order, or upon their own compulsion. In any event, five Americans lay

dead and several others seriously wounded.... Members of a distrusted standing army, whose

quartering was in violation of the Petition of Right, and whose preparation to militarily suppress

possible civil disorder was inconsistent with the oldest of England’s own traditions, had slain

English civilians in a time of peace.

19 This last charge presumably refers to the results of the murder trials of the officer and soldiers involved in the Boston

Massacre. Two of the soldiers were convicted of manslaughter, branded on the hand and released; the officer and the

other soldiers were acquitted. See ZOBEL, supra note 17, at 241-94.

20 See, e.g., ARTS. OF CONF. VI, VII, & IX.

No vessels of war shall be kept up in time of peace by any State, except such number only, as shall

be deemed necessary by the United States in Congress assembled, for the defence of such State, or

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The Constitution continued these themes, albeit with greater authority vested in the federal

government. It provided that a civilian (the President) should be the Commander in Chief of the

Army and Navy of the United States, and civilian authorities (Congress) should be solely

empowered to raise and support Armies, provide and maintain a Navy, and make rules for their

government and regulation.21 The Bill of Rights limited the quartering of troops in private

homes,22 and noted that “a well regulated Militia, being necessary to the security of a free State,

the right of the people to keep and bear Arms, shall not be infringed.”23 The Constitution, on the

other hand, explicitly permitted Congress to provide for calling out the militia to execute the

laws, suppress insurrection, and repel invasion.24

The Use of Federal Troops Prior to 1878

Notwithstanding the founders’ aversion to the use of a standing army to control the civilian

populace, the Constitution nowhere explicitly prohibits it, and Congress lost no time in

authorizing the President to call out the militia for the purposes permitted under the

Constitution.25 Despite the retention of most police powers by the several states, Congress quickly

established a law enforcement capability in the federal government in order to effectuate its

constitutional powers and provide a means to enforce the process of federal courts.26 This

authority was vested through the President in federal marshals, who were empowered to call upon

its trade; nor shall any body of forces be kept up by any State, in time of peace, except such number

only, as in the judgment of the United States, in Congress assembled, shall be deemed requisite to

garrison the forts necessary for the defence of such State; but every State shall always keep a well

regulated and disciplined militia, sufficiently armed and accoutered, and shall provide and

constantly have ready for public use, in public stores, a due number of field pieces and tents, and a

proper quantity of arms, ammunition and camp equipage.... When land-forces are raised by any

State for the common defence, all officers of or under the rank of colonel, shall be appointed by the

Legislature of each State respectively by whom such forces shall be raised, or in such manner as

such State shall direct, and all vacancies shall be filled up by the State which first made the

appointment.... The United States in Congress assembled shall never ... appoint a commander in

chief of the army or navy, unless nine States assent to the same....

21 U.S. CONST. art. II, § 2; art. I, § 8, cls. 12, 13, 14. The Constitution treats the militia similarly. The President is the

Commander in Chief of the militia while it is in federal service, and Congress is empowered to approve its

organization, arms and discipline, U.S. CONST. art. II, § 2; art. I, § 8, cl.16.

22 U.S. CONST. amend. III.

23 U.S. CONST. amend. II.

24 U.S. CONST. art. I, § 8, cl.15. Congress is further empowered to organize, arm, and discipline the militia, and to

govern any part of militia in federal service, but the power to appoint officers and train the militias remains with the

states. Id. cl. 16.

25 See Jay S. Bybee, Insuring Domestic Tranquility: Lopez, Federalization of Crime, and the Forgotten Role of the

Domestic Violence Clause, 66 GEO. WASH. L. REV. 1, 41-42 (1997) (describing the Militia Act of 1792, 1 Stat. 264).

26 Judiciary Act of 1789, Ch. 20, § 27, 1 Stat. 73, 87 (1789).

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the posse comitatus27 to assist them, an authority similar to that enjoyed by the sheriff at common

law,28 and which was understood to include the authority to call for military assistance.29

Thus, the militia under federal control (and later the Armed Forces30) could operate either as an

arm of the government or to support the federal marshal.31 These two roles of the military were

similar in many respects, but, at least in theory, differed in one key aspect: troops serving as a

posse comitatus remained subordinate to civil law enforcement authorities, while troops called up

to suppress an insurrection or remove an obstruction to the execution of the laws supplanted civil

authorities that had been rendered ineffective.32 In some cases, if the marshal feared he would be

unable to control a disturbance even with the aid of a posse, or if local military commanders

declined to give assistance, the marshal would try to persuade the President that an insurrection

was underway.33 At other times, the President might order troops to quell what appeared to

amount to an insurrection, yet limit the role of the Armed Forces to responding to the requests of

the appropriate civil official, possibly dispensing with the need to issue the requisite proclamation

under the Insurrection Act.34

In addition, Congress has from time to time enacted statutes authorizing federal troops to enforce

specific proscriptions, sometimes in aid of civil authorities and sometimes (apparently) in their

stead,35 and Presidents have issued proclamations exhorting all federal officials, civilian or

military, to assist in arresting a particular conspiracy or uprising.36 It is not always easy to

ascertain which statutory authority (if any) forms the basis for sending in federal troops.

27 The Latin phrase literally means attendants with the capacity to act from the words comes and posse meaning

companions or attendants (comes) and to be able or capable (posse). Among the Romans comitatus referred to one who

accompanied the proconsul to his province. Later, comes (sometimes referred to as comites or counts) meant the king’s

companions or his most trusted attendants and comitatus came to refer to the districts or counties entrusted to their care.

BOUVIER’S LAW DICTIONARY AND CONCISE ENCYCLOPEDIA 529, 2635 (1914).

28 At common law, the sheriff of every county was obligated “to defend his county against any of the king’s enemies

when they come into the land; and for this purpose, as well as for keeping the peace and pursuing felons, he may

command all the people of his county to attend him; which is call the posse comitatus, or power of the county; which

summons every person above fifteen years old, and under the degree of a peer, is bound to attend upon warning, under

pain of fine and imprisonment.” 1 BLACKSTONE, supra note 7, at 332.

29 Canestaro, supra, note 1, at 110 (observing that Judiciary Act of 1789 supported the Mansfield doctrine, which held

that federal marshals could employ military troops as a posse comitatus).

30 Engdahl, supra note 10, at 48-49 (describing how, after the Act of March 3, 1807, Ch. 39, 2 Stat. 443, permitted the

use of the army wherever the militia could be employed to respond to domestic violence, “regular forces came

increasingly to displace the militia as the principal instrument of arms in the nation, for marshals to employ regular

military troops rather than militia as their posse comitatus”).

31 Id. at 47-48.

32 Id. at 50 (“[C]ommon were the cases in which soldiers were called to aid civil officials in dispersing mobs or

suppressing riots precipitated by hotly contested elections or other public issues, or in other ways to assist the civilian

officers. It was well understood that when they were used under such circumstances the soldiers were used not in their

military character, but merely as civilian assistants subject to the command of the ordinary civil officers, and no more

privileged in their use of force against citizens than the civil officers were themselves.”).

33 See infra “The Use of Federal Troops Prior to 1878.”

34 Id.

35 See infra, note 224 (listing examples).

36 For example, to counter the infamous Burr conspiracy in 1806, President Jefferson issued a proclamation

“enjoin[ing] and requir[ing] all officers, civil and military, of the United States, or of any of the states or territories, and

especially all governors and other executive authorities, all judges, justices and other officers of the peace, all military

officers of the Army or Navy of the United States, or officers of the militia, to be vigilant, each within his respective

department and according to his functions, in searching out and bringing to condign punishment all persons engaged in

[a military expedition against Spanish territory], in seizing and detaining ... all vessels, arms military stores ... and in

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Presidents have relied upon the militia and Armed Forces with some frequency for riot control or

when in extreme cases they felt it necessary to ensure the execution of federal law.37 The

following sections provide an overview of the domestic employment of military forces and the

statutes that govern such use.

The Insurrection Act and Other Statutes

Soon after Congress was first assembled under the Constitution, it authorized the President to call

out the militia, initially to protect the frontier against “hostile incursions of the Indians,”38 and

subsequently in cases of invasion, insurrection, or obstruction of the laws.39 Shortly thereafter,

and echoing Article I, Section 8, cl. 15 and Article IV, Section 4 of the Constitution, Congress

enacted the Calling Forth Act, authorizing the President to call out the militia in case of invasion

or, at the request of a state legislature (or its governor, if the legislature could not be convened) in

case of an insurrection within a state.40 Congress also empowered the President to call forth the

militia, for a period of 30 days:

general in preventing the carrying on such expedition or enterprise by all lawful means within their power....”

FREDERICK T. WILSON, FEDERAL AID IN DOMESTIC DISTURBANCES, 1903-22, at 38, S. DOC. NO. 67-263 (1922)

(hereinafter “S. DOC. NO. 67-263”).

37 Eighteenth and nineteenth century instances are collected, along with related proclamations and other documentation,

in FREDERICK T. WILSON, FEDERAL AID IN DOMESTIC DISTURBANCES: 1787-1903, S. DOC. NO. 57-209 (1903); updated

to include early 20th century incidents in U.S. ARMY JUDGE ADVOCATE GENERAL, FEDERAL AID IN DOMESTIC

DISTURBANCES, 1903-22, S. DOC. NO. 67-263 (1922); see also BENNET MILTON RICH, PRESIDENTS AND CIVIL DISORDER

(1941); CLAYTON D. LAURIE AND RONALD H. COLE, THE ROLE OF FEDERAL MILITARY FORCES IN DOMESTIC DISORDERS:

1877-1945 (1997); PAUL SCHEIPS, THE ROLE OF FEDERAL MILITARY FORCES IN DOMESTIC DISORDERS, 1945-1992

(2005).

38 1 Stat. 96 (1789); 1 Stat. 121 (1790).

39 Calling Forth Act of 1792, ch. 28, 1 Stat. 264 (repealed 1795); the Militia Act of 1795, ch. 36, 1 Stat. 424 (repealed

in part 1861 and current version at 10 U.S.C. §§ 251-255). The constitutional and statutory authority to use military

force in case of insurrection seems to have been in direct response to a perceived weakness in government under the

Articles of Confederation. In 1787, a group of farmers in western Massachusetts, led by a Revolutionary War veteran

named Daniel Shays and feeling oppressed by tax and creditor protection policies within the Commonwealth, had

harassed the state courts and constabulary, and had attempted to storm the federal arsenal at Springfield before being

repulsed by the militia. Some saw the insurrection as evidence of the need for a stronger central government and

implicitly, confirmation that domestic tranquility might be more readily ensured if backed by centralized military

capability. See SAMUEL ELIOTT MORISON, ET AL., I THE GROWTH OF THE AMERICAN REPUBLIC 242 (7th ed. 1980)

(“Nevertheless, Shays’s Rebellion had a great influence on public opinion.... When Massachusetts appealed to the

Confederation for help, [the Continental] Congress was unable to do a thing. That was the final argument to sway many

Americans in favor of a stronger federal government”); CHRISTOPHER COLLIER & JAMES LINCOLN COLLIER, DECISION IN

PHILADELPHIA: THE CONSTITUTIONAL CONVENTION OF 1787, at 13 (1986) (“To men like Madison and Washington,

Shays’s Rebellion was an imperative. It hung like a shadow over the old Congress, and gave both impetus and urgency

to the Constitutional Convention. It was the final, irrefutable piece of evidence that something had gone badly wrong.

For some time these men had known that the deficiencies of the American government must be remedied. Shays’s

Rebellion made it clear to them that it must be done now.”); CATHERINE DRINKER BOWEN, MIRACLE AT PHILADELPHIA:

THE STORY OF THE CONSTITUTIONAL CONVENTION MAY TO SEPTEMBER 1787, at 10 (1966) (“Shays’s Rebellion had been

in the public mind when Congress, after debating the Annapolis report, had voted in favor of a convention in

Philadelphia.”).

40 Calling Forth Act of 1792, ch. 28, § 1, 1 Stat. 264 (repealed 1795 and current version now codified at 10 U.S.C. §

251 (2018)). It is unclear why Congress limited the ability of states to request assistance to circumstances of

insurrection rather than “domestic violence” as permitted in Article IV, Section 4 of the Constitution. Perhaps

“domestic violence” was interpreted to be restricted to violence of a sufficient magnitude to constitute an insurrection,

or the word “insurrection” was meant to convey armed violence that did not amount to a rebellion or revolution seeking

to overthrow the government in part or all of a state. See RICH, supra note 37, at 21 n. 1 (citing definition of

insurrection as including resistance to government authority smaller in scope and purpose than those described by the

terms “rebellion” and “revolution”).The guarantee of a “republican form of government” would seem to require federal

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whenever the laws of the United States shall be opposed, or the execution thereof

obstructed, in any state, by combinations too powerful to be suppressed by the ordinary

course of judicial proceedings, or by the powers vested in the marshals by this act, the same

being notified to the President of the United States, by an associate justice or the district

judge.41

In any of these events, the President was first required to issue a proclamation commanding the

“insurgents” to disperse.42 President Washington used this authority to put down the Whiskey

Rebellion in western Pennsylvania.43 Resistance to an excise tax on distilled whiskey led to

violence against tax collectors; indictments of those perpetrating the violence went unanswered,

and farmers eventually rose in rebellion against all efforts to enforce the federal law.44 The

governor, having declined to call out the state militia to control the violence, the federal courts

were left to call on the federal government for assistance.45 When the rioters failed to disperse on

the President’s proclamation, some fifteen thousand militiamen from Pennsylvania and

neighboring states quickly mobilized to restore the peace.46

After the Calling Forth Act expired two years later, Congress reenacted virtually the same

language, except that a court finding was no longer necessary, and the proclamation to disperse

did not have to occur prior to calling up the militia.47 It appears that the revised Calling Forth Act

was understood to cover the use of the militia as an aid to civilian power or, in rare cases, as a

means of temporarily supplanting local civilian authority.48

Both provisions of the Calling Forth Act were extended in 1807 to allow for the employment of

the Army and Navy in domestic circumstances where the militia could be employed.49 Even

before this change, President John Adams had used regular federal troops to put down, more by

intimidation rather than the actual use of force,50 the 1799 Fries Rebellion in eastern

Pennsylvania.51 The cavalry arrested the instigator of the resistance, John Fries, along with other

intervention in the event of a rebellion against a state government even without its request.

41 Id. § 2 (repealed 1795 and current version now at 10 U.S.C. § 252 (2018)).

42 Id. § 3 (repealed 1795 and current version now at 10 U.S.C. § 254 (2018)).

43 See Presidential Proclamations of Aug. 7, 1794 and Sept. 25, 1794, 1 JAMES D. RICHARDSON, A COMPILATION OF THE

MESSAGES AND PAPERS OF THE PRESIDENTS 158-62 (1896). For more information, see generally THOMAS P. SLAUGHTER,

THE WHISKEY REBELLION: FRONTIER EPILOGUE TO THE AMERICAN REVOLUTION (1986); STEVEN R. BOYD, THE WHISKEY

REBELLION: PAST AND PRESENT PERSPECTIVES (1985).

44 MARLIN S. REICHLEY, FEDERAL MILITARY INTERVENTION IN CIVIL DISTURBANCES 57 (1939).

45 Id. at 58.

46 Id. (noting the militia were called out from Pennsylvania, Virginia, Maryland, and New Jersey).

47 The Militia Act of 1795, ch. 36, 1 Stat. 424 (repealed in part 1861).

48 See Engdahl, supra note 10, at 49-50 (noting that prior to the Civil War, military troops were more commonly

employed to assist civil officers in the enforcement of civilian laws rather than as soldiers privileged to use force).

49 The Insurrection Act of 1807, ch. 39, 2 Stat. 443 provided that:

in all cases of insurrection, or obstruction to the laws, either of the United States, or of any

individual state or territory, where it is lawful for the President of the United States to call forth the

militia for the purpose of suppressing such insurrection, or of causing the laws to be duly executed,

it shall be lawful for him to employ, for the same purposes, such part of the land or naval force of

the United States, as shall be judged necessary, having first observed all the pre-requisites of the

law in that respect.

50 See RICH, supra note 37, at 25-26 (noting lack of resistance to armed troops, whose presence terrorized local

inhabitants, partly due to the inability of the commanding general to maintain strict discipline among his troops).

51 Proclamation of March 12, 1799, reprinted in S. DOC. No. 67-263, supra note 36, at 35.

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participants, and turned them over to civil authorities to be tried for treason. Those convicted

were eventually pardoned.52

Resistance to Taxes and Duties

As in the Whiskey and Fries Rebellions, resistance to the laws of the United States during the

early years of the republic had mainly to do with citizens’ objections to steadily increasing federal

taxes, which were largely necessary to build up the military establishment,53 and other laws that

tended to make themselves felt in citizens’ pocketbooks. In 1808, President Jefferson called out

federal troops to suppress opposition to the Embargo Act54 by groups of traders in Vermont whose

livelihood depended on imports and exports with Canada.55 Although President Jefferson

followed the contemporary practice of turning to states’ governors to supply militia in support of

revenue collectors, the state militia troops proved reluctant to enforce the law against their

neighbors, so the President sent in a detachment of regular troops to restore order.56 Congress

subsequently amended the Embargo Act specifically to authorize the use of troops to enforce the

embargo.57 Resentment at the newly enacted authority to use federal military force to enforce

ordinary laws in the absence of armed resistance led to a speedy demise of the embargo statute.58

In 1832, resistance to revenue laws again led to the prospect of using federal troops.59 Southerners

objected to the system of protective tariffs that had been adopted in 1816 after the post-war

resumption of trade threatened new domestic industries.60 Rather than gradually reducing the

tariffs, as it had indicated was its intent, Congress steadily increased the tariff until by 1832 it

became a policy fixture.61 Southerners believed that the money was raised unfairly at their

expense and was expended mainly for the benefit of Northerners.62 The legislature of South

Carolina voted to nullify the tariff and declared the state ready to meet force with force in the

event the federal government sought to collect the tax.63 Congress passed a “Force Bill” to

52

Proclamation of May 21, 1800, reprinted in S. DOC. No. 67-263, supra note 36, at 36.

53 See RICH, supra note 37, at 21 (attributing need for increased revenue to pending war with France).

54 2 Stat. 451 (1807).

55 S. DOC. NO. 67-263, supra note 36, at 40-44. The federal marshal was to attempt to enforce the law with the use of

the posse comitatus, and if that failed, the Secretary of War was to request the governor to issue a proclamation

furnished by the President and then call on the state militia. Id. at 41. The President’s proclamation to disperse drew ire

from the local population, which drew up their own memorial protesting the characterization of the situation as an

“insurrection and rebellion.” RICH, supra note 37, at 32. When similar opposition to the embargo arose in New York,

the President did not issue a proclamation, attempting instead to persuade the governor to take action, but promising to

reimburse the state for its assistance in enforcing federal law. Id. at 33.

56 REICHLEY, supra note 44, at 64.

57 2 Stat. 506, 510 (1809) (also known as the “Force Bill”) (repealed).

58 See ROBERT W. COAKLEY, THE ROLE OF FEDERAL MILITARY FORCES IN DOMESTIC DISORDERS, 1789-1878, at 89

(1989). Congress replaced the Embargo Act with a new measure to interdict trade with Great Britain and France, 2 Stat.

528, which authorized military force to compel ships from those countries to depart U.S. ports but did not permit the

use of federal or state military forces to prevent any illicit trade.

59 Id. at 96 (reporting that President Jackson faced the prospect of employing military force in a state that opposed

enforcement of federal law).

60 See RICH, supra note 37, at 38-39.

61 Id.

62 See COAKLEY, supra note 58, at 95 (stating that Southerners, who sold cotton and other staples abroad but also

imported heavily, found the measure discriminatory for protecting Northern interests, in their view amounting to an

unconstitutional federal regulation of domestic industry).

63 RICH, supra note 37, at 38-39; ANDREW JACKSON, COPIES OF THE PROCLAMATION AND PROCEEDINGS IN RELATION TO

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authorize the President to use the Army and Navy to collect duties,64 but at the same time reduced

the duties.65 South Carolina rescinded its nullification ordinance, bringing the confrontation to an

end without the use of force (although, as a final defiant gesture, it issued a new ordinance to

nullify the Force Bill).66

Neutrality Act Enforcement

The early U.S. desire to avoid foreign entanglements of the sort that kept Europe in arms during

the founders’ era manifested itself in a policy of neutrality which tended, at times, to conflict with

the economic interests or political views of some part of the citizenry.67 Congress enacted a

statute to prohibit the enlistment in or recruitment for foreign military service, the arming of

foreign war vessels or privateers, and the dispatch of military expeditions against the territory of a

state at peace with the United States.68 The statute also empowered the President to call upon the

Armed Forces to detain or take possession of illicitly armed vessels and to prevent expeditions

from departing U.S. territory.69 Even prior to its enactment, President Washington had called on

state militias to deal with efforts of the French Ambassador to fit out privateers and military

expeditions against British and Spanish interests.70 President Jefferson relied on this authority to

counter Aaron Burr’s conspiracy in 180671 as well as other schemes to liberate Spain’s South

SOUTH CAROLINA, S. DOC. NO. 22-30, at 38 (1833).

64 Act of March 2, 1833, ch. 57 § 1, 4 Stat. 632, (authorizing the President “to employ such part of the land or naval

forces, or militia of the United States, as may be deemed necessary for the purpose of preventing the removal of such

vessel or cargo…”); Id. § 5, 4. Stat. 634 (providing that “whenever the President of the United States shall be officially

informed, by the authorities of any state … that, within the limits of such state, any law or laws of the United States, or

the execution thereof, or of any process from the courts of the United States, is obstructed by the employment of

military force, or by any other unlawful means, too great to be overcome by the ordinary course of judicial proceeding,

or by the powers vested in the marshal by existing laws, it shall be lawful for him, the President of the United States,

forthwith to issue his proclamation, declaring such fact or information, and requiring all such military and other force

forthwith to disperse; and if … such opposition or obstruction shall be made … the President shall be … authorized,

promptly to employ such means to suppress the same, and to cause the said laws or process to be duly executed, as are

authorized and provided in the cases therein mentioned by the [Calling Forth Act]”).

65 Act of July 14, 1832, ch. 227, 4 Stat. 583, amended by Act of March 2, 1833, ch. 58, 4 Stat. 636 (reducing certain

tariffs).

66 REICHLEY, supra note 44, at 67.

67 See generally CHARLES FENWICK, THE NEUTRALITY LAWS OF THE UNITED STATES 15-18 (1913) (describing political

situation accompanying President Washington’s neutrality proclamation and early neutrality statutes).

68 Act of June 5, 1794, 1 Stat. 381, renewed, 1 Stat. 497 (March 2, 1797) and 2 Stat. 54 (April 24, 1800), repealed 3

Stat. 447, 450 (1818)).

69 Id. § 7, 1 Stat. 384.

70 See COAKLEY, supra note 58, at 25-26 (describing government circulars to governors requesting militia support to

suppress neutrality violations).

71 See supra note 36; Thomas Jefferson, Message to Congress on the Burr Conspiracy, January 22, 1807, available

online at The American Presidency Project, http://www.presidency.ucsb.edu/ws/?pid=65721 (“Orders were dispatched

to every interesting point on the Ohio and Mississippi from Pittsburg to New Orleans for the employment of such force

either of the regulars or of the militia and of such proceedings also of the civil authorities as might enable them to seize

on all the boats and stores provided for the enterprise, to arrest the persons concerned, and to suppress effectually the

further progress of the enterprise.”); Thomas Jefferson, Sixth Annual Message, December 2, 1806, available online at

The American Presidency Project, http://www.presidency.ucsb.edu/ws/?pid=29448 (suggesting additional statutory

authority for prevention of such expedition might be in order). The President’s desire to employ federal troops along

with state militia led him to use the neutrality law rather than the Insurrection Act, although President believed the

conspiracy amounted to an insurrection aimed at separating western territories from the United States. See COAKLEY,

supra note 58, at 83. The Insurrection Act was thereafter amended to permit the use of regular troops as well as militia.

Id. (citing 2 Stat. 443 (1807)), see supra note 49.

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American colonies.72 State militias employed for this purpose remained under the control of their

respective governors.73

In 1836, at the time of Texas’s struggle for independence from Mexico, the Armed Forces were

employed in an effort to prevent armed American sympathizers from crossing the border to join

the fight74 in violation of the Neutrality Act of 1818,75 which expressly authorized the

employment of the militia and Armed Forces in its enforcement. The next year, the Army was

employed in a similar vein to quiet militant activity along the Canadian border.76 President

Zachary Taylor issued a proclamation urging all officials, “civil and military,” to halt a planned

expedition to attack Cuba,77 which resulted in the Navy dispatching vessels to New Orleans to

prevent the expedition from departing.78 To block American sympathizers from aiding Cuban

separatists during the Ten Years’ War and to halt Fenian expeditions against Canada, President

Grant issued a proclamation in 1870 urging civil and military officers to take measures to prevent

expeditions in violation of neutrality and to bring violators to justice.79

Requests from States for Military Aid

Section 2 of the Calling Forth Act, authorizing the President to employ military force when the

state made a proper application for assistance, lay dormant until the 1830s, when violence

between contending groups of Irish laborers on the Chesapeake and Ohio Canal led Maryland’s

legislature to request federal aid in 1834.80 President Jackson promptly endorsed the request to the

Secretary of War and ordered “at least two companies of regulars” be sent to aid state civil

72 FENWICK, supra note 67, at 32-33 (describing Francesco de Miranda’s efforts to organize expeditions). Two

Americans charged with violating the Neutrality Act in connection with the expedition attempted to set up a defense

that their actions were undertaken on behalf of the U.S. government, but the judge refused to issue summons to various

public officials, ruling that the actions were unlawful regardless whether they had been authorized by the President. Id.

at 33 (citing United States v. Smith, 27 F. Cas. 1192, 1231 (C.C.D.N.Y. 1806)). The defendants were acquitted by a

jury. Id.

73 S. DOC. NO. 67-263, supra note 36, at 39.

74 Id. at 49-50.

75 Neutrality Act of April 20, 1818, § 8, 3 Stat. 447, 449. Prior to enactment of the 1818 statute, the general practice

entailed a presidential appeal to state governors for aid in arresting violators. See VII JOHN BASSET MOORE, DIGEST OF

INTERNATIONAL LAW § 1321 (1906). After enactment of the 1818 Act, the President called on district attorneys and

U.S. marshals or on states’ attorneys-general to assist in enforcement, see id., sometimes with the aid of military forces.

76 S. DOC. NO. 67-263, supra note 36, at 51-53.

77 V JAMES D. RICHARDSON, A COMPILATION OF THE MESSAGES AND PAPERS OF THE PRESIDENTS 7-8 (1897).

78 The first of the so-called filibuster expeditions led by Narciso Lopez was disbanded without force by the Navy and

civil authorities in 1849. See Louis N. Feipel, The Navy and Filibustering in the Fifties, 44 U.S. NAVAL INST. PROC.

767, 769 (1918). A second expedition in 1851 evaded U.S. naval forces only to have two of its vessels captured by

Spanish men-of-war, but the captured filibusterers were eventually released back to American forces after some

diplomatic exchange. Id. at 1016, 1027. A third expedition managed to land in Cuba in 1851 but was not met with local

enthusiasm according to plan and was defeated, ending in the trial and execution of the main instigators. Id. at 1027-29.

The Fenian Brotherhood was an organization of Irish-Americans some 15,000 strong by 1863 whose object it was to

secure the independence of Ireland from Great Britain. After the Civil War ended, a Fenian military convention

determined to invade Canada, but the U.S. military intervened to seize a vessel laden with arms and ammunition, thus

frustrating the planned expedition. S. DOC. NO. 67-263, supra note 36, at 94.

79 Proclamation of Oct. 12, 1870, 16 Stat. 1136; FENWICK, supra note 67, at 52 (stating object of proclamation).

80 See COAKLEY, supra note 58, at 105.

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authorities, without, however, issuing a proclamation to the laborers to disperse.81 The presence of

federal troops helped to stabilize the situation without requiring any actual use of force.82

A second request was occasioned in 1838, when both parties to the Pennsylvania state election

claimed victory and set about to establish majority control of the state House. When public

reaction turned violent, the governor called out the militia and requested aid from the local

military commander, who denied the request.83 The governor then appealed to President Van

Buren for federal assistance under the Domestic Violence Clause of the Constitution.84 Despite

that clause’s guarantee of protection, President Van Buren took the position that his duty was

discretionary, and believing the domestic violence was not of a character that the “State

authorities, civil and military ... have proved inadequate to suppress it,” he declined to authorize

assistance.85 In the meantime, however, the commanding general of the U.S. arsenal at Frankford

brought men and ordnance in response to the governor’s request.86 The “Buckshot War” ended

without armed confrontation, but the commander was reprimanded by the War Department for

acting without authorization.87

A more serious state of affairs was reached in Rhode Island in 1842, where dissatisfaction with

the government under the state’s charter, still that granted by King Charles II in 1663, led to

efforts to draft a new constitution.88 Two separate conventions were established, resulting in two

separate sets of government officials claiming legitimate authority.89 The governor under the

charter declared martial law and requested the President provide federal troops to stop the feared

violence, but President Tyler declared he had no power to anticipate insurrections.90 Three

subsequent similar requests were similarly denied.91 By the time the President had decided that

intervention might be necessary to prevent the opposition army (led by contending Governor

Thomas Dorr) from using force, the Secretary of War had determined that Dorr’s men had

dispersed, and the already-prepared proclamation would not be necessary.92

The “Dorr Rebellion” had ended without a clash of arms.93 It did, however, produce a seminal

Supreme Court decision, Luther v. Borden.94 In Luther, among other things, the Court established

that whether a state enjoys a republican form of government guaranteed by the Constitution was a

political matter for Congress to decide.95 Moreover, the Court indicated that Congress having

81 Id.

82 Id. at 105-06.

83 RICH, supra note 37, at 53.

84 COAKLEY, supra note 58, at 108.

85 RICH, supra note 37, at 53-54.

86 COAKLEY, supra note 58, at 109.

87 RICH, supra note 37, at 53; COAKLEY, supra note 58, at 109 (recounting that the Secretary of War laid down the

general rule, that “[i]n doubtful cases where the seat of government is near the theater of the disturbance, the necessity

must be very urgent and palpable to justify an officer commanding a detached post in marching his forces to repress an

insurrection without authority to do so from this department”).

88 S. DOC. NO. 67-263, supra note 36, at 53-54.

89 Id. at 54.

90 Id.

91 Id. at 55-56.

92 Id. at 57.

93 Id. (quoting President Tyler’s message to Congress).

94 Luther v. Borden, 48 U.S. 1 (1849).

95 Id. at 42 (“Under [Art. IV § 4] of the Constitution it rests with Congress to decide what government is the established

one in a State. For as the United States guarantee to each State a republican government, Congress must necessarily

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delegated to the President its prerogative to call forth the militia in cases of domestic violence, it

is up to the President to determine the exigency of responding to a call from a state for military

intervention to put down a claimed insurrection.96 In either case, the Court determined the

judiciary has no role to play.97

After the Civil War, labor disputes led to numerous requests for federal troops to suppress

violence.98 In 1877, in response to strikes and related violence that erupted after railroads cut the

pay of their workers by 10%, federal troops were requested by the governors of Pennsylvania,99

West Virginia,100 Maryland,101 Illinois,102 and Missouri, Indiana,103 Wisconsin, California, and

Kentucky,104 with varying degrees of conformity to the requirements of the Insurrection Act, as

interpreted by President Hayes.105 Although Ohio’s governor did not request federal troops to

quell strike-related violence in Toledo, Cincinnati, and other places, local officials appealed for

assistance from nearby military commanders.106 No direct help was given, although supplies of

arms from Rock Island Arsenal were made available to the state.107 It has been suggested that

federal authority might have been asserted on the basis of the protection of a federal function (i.e.,

the delivery of the mail), but either due to an understanding that federal assistance to enforce state

law was constitutionally unavailable without the request of the state government, or due to the

lack of available federal troops, the President made no effort to do so.108

decide what government is established in the State before it can determine whether it is republican or not…. And its

decision is binding on every other department of the government, and could not be questioned in a judicial tribunal.”).

96 Id. at 43 (“[T]he power of deciding whether the exigency had arisen upon which the government of the United States

is bound to interfere, is given to the President. He is to act upon the application of the legislature or of the executive,

and consequently he must determine what body of men constitute the legislature, and who is the governor, before he

can act.”).

97 Id. at 42-43.

98 See JERRY M. COOPER, THE ARMY AND CIVIL DISORDER 1 (1980) (reporting on the rise of trade unions after the Civil

War and stating that by 1877 “industrial conflict was a permanent part of the American scene”).

99 RICH, supra note 37, at 74-75. Pennsylvania militia sent to suppress a riot in Pittsburgh instead inflamed the situation

and were forced to withdraw, leaving the city in anarchy. Id.

100 The insurrection involved striking railroad workers, who seized control of the railroad in Martinsburg, WV. See

RICH, supra note 37, at 73. The President sent federal troops, instructing their commanders not to act until his

proclamation to disperse had been published. See S. DOC. NO. 67-263, supra note 36, at 163; 20 Stat. 803-04

(proclamation).

101 A confrontation between militia and strike sympathizers in Baltimore, which resulted in 10 deaths, was the impetus

for sending in troops. See RICH, supra note 37, at 74; 20 Stat. 804 (proclamation).

102 The Illinois governor requested assistance in the proper form, and President Hayes promptly promised to supply it,

but apparently not wanting to issue a proclamation, gave orders that troops were to be used to protect government

property and enforce the orders of federal courts. See RICH, supra note 37, at 80.

103 S. DOC. NO. 67-273, supra note 36, at 171-72.

104 See RICH, supra note 37, at 80-81. The disturbance in California resulted from resentment against Chinese

immigrants.

105 See id. at 78 (listing the President’s criteria for a formal request, which consisted of a certification that (1) disorder

existed; (2) state authorities were incapable of preserving the peace; (3) the legislature was not in session; (4) the

legislature could not be convened in time to meet the emergency; and (5) the appeal to the President was to protect the

state against domestic violence).

106 See S. DOC. NO. 67-263, supra note 36, at 170 (reporting that General Hancock determined that such assistance was

not authorized, the governor not having requested it, unless troops were formally summoned by the sheriff as a posse

comitatus).

107 Id.

108 See RICH, supra note 37, at 82-83.

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Questions regarding the federal versus state control of troops arose during the 1877 riots.109 In

West Virginia and Maryland, federal troops were placed under the command of the governors to

be employed alongside state troops.110 In Indiana, where the governor’s request was initially

turned down for lack of compliance under the Constitution and Insurrection Act,111 federal troops

were to be furnished on the request of the federal marshal as a posse comitatus and were not

turned over to the governor.112 When disorder spread to Pennsylvania, federal troops were

initially sent in to protect federal property, the governor’s first request for assistance having

apparently been deemed deficient.113 After the deficiencies were corrected and a proclamation

was issued, the general officer in charge of federal troops requested clarification as to the

disposition of federal troops114 and espoused the doctrine that whenever a state government asks

for assistance under the Insurrection Act, federal military power should supplant local civil

authority:

When the governor of a State has declared his inability to suppress an insurrection and has

called upon the President of the United States under the Constitution to do so, that from

that time commences a state not of peace but of war, and that although civil local authority

still exists, yet the only outcome is to resort to force through the Federal military

authorities, and that can only be through a subordination of the State authorities for the

time being and until lawful order is restored; otherwise there can be no complete exercise

of power in a military way within the limits of the State by the Federal officers.115

The doctrine appears to have gained the approval of President Hayes, at least insofar as it had to

do with command of state troops, although a telegram advising the commander to in effect

federalize state troops arrived too late to be carried into effect.116 The proposed equation of

insurrection to war calling for the substitution of military force for ordinary methods of law

enforcement seems to have found its way into later War Department manuals regarding the

military role in civil disturbances.117

109 See COOPER, supra note 98, at 62-64.

110 Id. at 62.

111 S. DOC. NO. 67-273, supra note 36, at 171-72. Although no proclamation under the Insurrection Act was issued,

President Hayes ordered that officers in charge were to command insurgents to disperse prior to taking any action. Id.

at 172.

112 Id. at 173

113 See RICH, supra note 37, at 78.

114 Telegram from Major-General Hancock to Adjutant-General of the Army, July 24, 1877, reprinted in S. DOC. NO.

67-263, supra note 36, at 275.

115 Telegram from Major-General Hancock to Secretary of War George W. McCrary, July 24, 1877, reprinted in S.

DOC. NO. 67-263, supra note 36, at 275, 276.

116 See RICH, supra note 37, at 76-77.

117

See, e.g., War Department Document No. 882, Office of the Adjutant General, Military Protection The Use of

Organized Bodies in the Protection and Defense of Property During Riots, Strikes, and Civil Disturbances 63 (1919)

(stating that “federal troops can not take orders from civil authorities” and that “a degree of martial law actually exists

whenever Federal troops go on duty” for the purpose of riot duty, even where martial law has not been declared); see

also A Comprehensive Study of the Use of Military Troops in Civil Disorders with Proposals for Legislative Reform, 43

U. COLO. L. REV. 399, 410 (1972) (arguing that the use of military after the Civil War led to erosion of notion that

military troops used to execute laws were ordinarily subordinate to civil authority). This phenomenon may have been

more pronounced at the state level. See Henry Winthrop Ballantine, Unconstitutional Claims of Military Authority, 5 J.

AM. INST. CRIM. L. & CRIMINOLOGY 718 (1915) (reporting instances of military intervention in labor disputes, mostly

by state militias).

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Trouble in the Western States and Territories

U.S. troops were sent to deal with disputes in western territories and new states on several

occasions. In California, the failure of the governor to request assistance under the Insurrection

Act led to a denial of military assistance.118 The California Gold Rush was marked by a

heightened tendency toward lawlessness, which was for a time brought under relative control by

vigilantes.119 The self-appointed Vigilance Committee of San Francisco, which had been allowed

to operate separately from federal and local law enforcement authorities, refused to surrender a

prisoner to the federal court under a writ of habeas corpus.120 The governor called out the militia

to put down the insurrection, and, having received a less than enthusiastic response, requested

assistance from the Army, and when that was refused, from the President.121 The Attorney

General advised the President that the situation was not sufficiently dire to require federal

intervention,122 and noted that during the month of turmoil said to require armed intervention, no

effort had been made to convene the legislature.123 When the Vigilante Committee took another

prisoner, a judge of the California Supreme Court, the state governor again requested assistance

from the military, this time from the commander of a ship in the harbor.124 Again, the request was

turned down. The senior naval commander in San Francisco, stressing the constitutional

requirements for requesting aid from the federal government to put down domestic violence,

instructed the ship’s captain that there was to be no interference in the domestic troubles of the

state.125

The territory of Utah was the site of considerable resistance to federal law after it was established

in 1850, and Brigham Young, the head of the Church of Jesus Christ of Latter-day Saints,

appointed its governor.126 Most white inhabitants of Utah were also members of the Church and

tended to regard laws not emanating from the governor to be invalid, eventually compelling

nearly all federal officials to leave the territory for their own safety.127 In 1857, the President

appointed a new governor, and federal Armed Forces were sent in to ensure a peaceful transfer of

power.128 Governor Young responded by declaring martial law and forbidding any Armed Forces

from entering the territory.129 It was not until April 1858 that President Buchanan issued a

proclamation offering amnesty to those who would obey the law and promising to prosecute those

who did not.130 The proclamation was not styled as an order to disperse, and troops were

instructed to act in aid of the execution of civil power.131

118 S. DOC. NO. 67-263, supra note 36, at 74.

119 Id. at 71.

120 Id. at 74-77.

121 Id. at 74.

122 Id. at 72-76, 247.

123 Id. at 249.

124 S. DOC. NO. 67-263, supra note 36, at 76.

125 Id. at 77.

126 Id. at 78.

127 Id. at 78 (citing H.R. EX. DOC. NO. 25, 32d Cong., 2d sess.).

128 Id. (federal forces were originally to act as posse comitatus to aid newly appointed civilian government).

129 Id. at 79.

130 Proclamation of April 6, 1858, 11 Stat. 796.

131 Id., 11 Stat. at 797 (reporting that the President had ordered a “detachment of the army to march for the City of Salt

Lake … and to act in case of need as a posse for the enforcement of the laws”).

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Slavery, the Civil War, and Reconstruction

In 1831, federal troops were sent out on several occasions to respond to reports of slave

insurrections, initially in New Orleans and later in Virginia, Maryland, Delaware, and the

Carolinas.132 These actions appear to have been undertaken by the local military commandants in

response to requests from local officials, and do not appear to have been justified by any statute

or presidential proclamation.133

During troubles related to the slavery issue in Kansas in 1856, President Pierce issued a

proclamation commanding persons involved in unlawful combinations to disperse.134 In the

following months, the new governor sent frequent requests to the commandants at Ft.

Leavenworth and Ft. Riley for troops to disband a territorial militia that had formed in

Lawrence.135 When Kansas’s pending entry into the Union in 1858 again brought tensions to a

head, the governor called upon the commander of U.S. troops for troops to act “as a posse

comitatus in aid of the civil authorities.”136 There does not appear to have been another

proclamation under the Insurrection Act, and since only the federal marshal and his deputies were

empowered to request the assistance of the military as a posse comitatus, there was no statutory

basis for this action. Rather, it appears to have been an exercise of the newly emerging theory

known as the Cushing Doctrine, explained below, under which members of the Armed Forces

could act as a posse comitatus to enforce the law without invoking the Insurrection Act or other

law that permitted the use of the Armed Forces.

At the dawn of the secessionist movement that led to the Civil War, President Buchanan declined

to send troops into seceding states, apparently based on his perception that any troops dispatched

to execute the laws of the Union would necessarily be subordinate to civil authorities.137 He

informed Congress that because federal law enforcement and judicial machinery in those areas

had already been demolished, his duty to execute the law could not be accomplished even with

the aid of military troops.138 On coming into office, President Lincoln took a very different view,

at times using federal military power without subordination to civil authority even in loyal Union

states.139 Congress also enacted a new provision to replace § 2 of the Calling Forth Act, adding

“rebellions” to instances for which the use of the Armed Forces was envisioned and to change the

standard from a situation in which a combination or obstruction to law enforcement was “too

powerful to be suppressed by the ordinary course of judicial proceedings” to one in which the

unlawful obstruction or assemblage “make[s] it impracticable to enforce the laws ... by the

ordinary course of judicial proceedings.”140

The successful suppression of the rebellion did not put an end to violence in the South. The

Reconstruction period after the Civil War was characterized by constant political turbulence in the

South.141 Efforts to establish new governments in former Confederate states were particularly

132 S. DOC. NO. 67-263, supra note 36, at 45-46, related documents at 223-25.

133 Id.

134 11 Stat. 791 (1856).

135 S. DOC. NO. 67-263, supra note 36, at 69-71.

136 Id. at 71.

137 See Engdahl, supra note 10, at 53.

138 See id.

139 Id. at 53-54. The Supreme Court declared such use of the military in loyal states to be unconstitutional. Ex parte

Milligan, 71 U.S. (4 Wall.) 2 (1866).

140 Act of July 29, 1861, 12 Stat. 281. See Engdahl, supra note 10, at 55-56 (describing changes).

141 See Gary Felicetti and John Luce, The Posse Comitatus Act: Setting the Record Straight on 124 Years of Mischief

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contentious during the decade following the Civil War, and Presidents received more requests for

military aid from state governors during these years than all previous decades combined,

sometimes receiving simultaneous requests from two rival governors claiming legitimacy in the

same state after an election.142

Resistance to efforts to achieve equal status for newly freed slaves led Congress to pass the Civil

Rights Act of 1871 (also called the “Ku Klux Klan Act”),143 which among other things added a

new insurrection provision permitting the President to employ the land and naval forces to

enforce civil rights. This authority was used immediately after enactment when President Grant

issued a proclamation calling attention to the new law and declaring himself ready to invoke it if

necessary.144 This was followed several months later by a proclamation under the new act

commanding conspirators in nine counties in South Carolina to disperse within five days and turn

in their firearms, ammunition, and disguises to the local marshals or military officers,145 and

shortly thereafter by a proclamation suspending habeas corpus, as permitted under Section 4 of

the act.146 Hundreds of suspected Klansmen were arrested over the following months and tried in

federal court.147

Use of Military Forces as a Posse Comitatus

Even though Congress had since 1792 empowered the President to call out the state militia to

overcome obstructions to law enforcement and it had also provided authority in a number of

statutes for the President to employ the land and naval forces for certain law enforcement

purposes, it appears to have been understood that federal law enforcement officials could

themselves call on local military commanders for assistance without involving the President.148

Congress had vested the federal equivalent of the sheriff, the federal marshal, with the power to

call forth the posse comitatus in performance of his duties.149 The federal marshals and their

deputies were thus implicitly empowered to compel the assistance of members of the Armed

Forces when force became necessary to execute the process of federal courts, but the military

and Misunderstanding Before Any More Damage Is Done, 175 MIL. L. REV. 86, 100-09 (2003) (describing “counterreconstruction” efforts and widespread racial terrorism); S. DOC. NO. 67-263, supra note 36, chapters V – VIII

(describing employment of military during Reconstruction period and post-Reconstruction political disturbances during

the years between 1866 and 1876).

142 See COAKLEY, supra note 58, at 341.

143 17 Stat. 13 (1871) (current version codified at 10 U.S.C. § 253).

144 17 Stat. 949 (1871). A previous proclamation under the existing authority to assist states South Carolina in putting

down domestic violence on application of the governor did not bring about the desired result, 16 Stat. 1138 (March 24,

1871).

145 17 Stat. 950 (1871).

146 17 Stat. 951 (1871).

147 S. DOC. NO. 67-263, supra note 36, at 103.

148 Felicetti & Luce, supra note 141, at 95 (“The framers clearly were aware of the posse comitatus and the use of the

military in some forms of law enforcement, yet they did not prohibit the practice.”).

149 See, e.g., 1 Stat. 87 (1789) (“a marshal shall be appointed in and for each district ... whose duty it shall be ... to

execute throughout the district, all lawful precepts directed to him, and issued under the authority of the United States,

and he shall have the power to command all necessary assistance in the execution of his duty....”); Calling Forth Act, §

9, 1 Stat. 265 (1792) (“the marshals of the several districts and their deputies shall have the same powers in executing

the laws of the United States, as sheriffs and their deputies in the several states have by law, in executing the laws of

their respective states”).

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units serving on a posse were to remain subordinate to the marshal and could not initiate legal

proceedings.150

In some cases when it passed a particular statute, Congress specifically authorized recourse to the

posse comitatus for its enforcement. The Fugitive Slave Act151 was such a law, and its use led to

the crystallization of the government’s doctrine regarding the use of the military in the role of a

posse.152 Under that act, owners whose slaves had escaped to another state were entitled to an

arrest warrant for the slaves and to have the warrant executed by the federal marshals. The

marshals in turn might “summon and call to their aid the bystanders, or posse comitatus of the

proper county ... [and] all good citizens [were] commanded to aid and assist in the prompt and

efficient execution of this law, whenever their services may be required, as aforesaid, for that

purpose.”153 The act did not specifically authorize the use of the military or militia in its

execution, but when particularly fierce opposition arose in Boston in 1851, the President issued a

proclamation requiring “all officers and persons, civil and military to aid and assist by all means

in their power in quelling [such] combinations.... ”154 The Secretary of War sent orders to Army

units to be ready to respond to the call of a marshal or deputy, or the certification of a federal

judge stating that military force would likely be necessary.155 Troops in Boston Harbor were made

ready to intervene in the event of a riot, but such intervention was unnecessary.156

When asked by the Senate whether sufficient authority for vigorous enforcement of the Fugitive

Slave Act was available, President Fillmore advanced the doctrine that his use of the Army and

Navy to enforce federal law was an inherent power, suggesting that it ought not be construed as

restricted by the Insurrection Act’s requirements, in particular that of issuing a proclamation to

disperse.157 He also made the argument that all citizens, whether enrolled in any military service

or not, may be summoned as a posse comitatus, while conceding doubt as to whether an

organized military force acting under military command might be employed in such a manner.158

The Senate Judiciary Committee declared that it saw no reason to consider military members

exempt from duty to serve as a posse comitatus, whether as individuals or organized under their

ordinary command structure.159

150 See WILLIAM WINTHROP, MILITARY LAW AND PRECEDENTS 866 (1920).

151 Act of Feb. 12, 1793, Respecting fugitives from justice, and persons escaping from the service of their masters, 1

Stat. 302, as amended by 9 Stat. 462 (1850).

152 Laws permitting the President to use military forces to execute particular laws were apparently understood to place

the forces so employed under the direction of civil authorities. See, e.g., Neutrality Act of April 30, 1818, § 8-9, 3 Stat.

447, 449 (authorizing President or his designee to employ militia or land or naval forces to detain certain vessels,

prevent military expeditions, and compel departure of foreign ships). In 1849, President Taylor used this authority to

call upon “every officer in the military, civil or military, to use all efforts in his power to arrest for trial and punishment

every such offenders of [neutrality laws, with respect to an expedition to invade Cuba],” V JAMES D. RICHARDSON, A

COMPILATION OF THE MESSAGES AND PAPERS OF THE PRESIDENTS 7-8 (1907).

153 9 Stat. at 463.

154 S. DOC. NO. 67-263, supra note 36, at 62; 9 Stat. 1006 (President Millard Fillmore’s proclamation urging all

officers, civil and military, to assist in enforcement of the Fugitive Slave Act in 1851).

155 S. DOC. NO. 67-263, supra note 36, at 62.

156 See COAKLEY, supra note 58, at 133.

157 Id. at 130 (citing VI JAMES D. RICHARDSON, A COMPILATION OF THE MESSAGES AND PAPERS OF THE PRESIDENTS

2637-46 (1897)). He further suggested that the requirement to issue a proclamation in connection with calling forth the

militia should be dispensed with in cases where such a proclamation might defeat the purpose of the law to be executed

by alerting persons whose arrest was sought.

158 Id.

159 Id.; S. REP. NO. 31-320 (1851). The Committee suggested that statutory authority to call forth the military or the

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In June of 1851, a federal marshal in Chicago arrested a fugitive slave on a warrant issued under

the act.160 He called for the assistance of members of the police force and of the state militia to

prevent abolitionists from rescuing the prisoner before he could be returned to his owner.161 The

marshal subsequently filed a claim with the Department of the Treasury for reimbursement of the

funds he had paid the members of the police force and the militia who responded to his call.162

Attorney General Caleb Cushing was asked whether the United States was obligated to honor the

claim.163 While this question remained pending, another incident in Boston arose in response to

the arrest of fugitive slave Anthony Burns in 1854.164 Two batteries of artillery and a detachment

of federal troops were sent into the city while the governor also called up the local militia,165 but

when additional forces were requested, military commanders considered further authorization

from Washington to be necessary before complying with the requests.166

The Attorney General took the opportunity, ostensibly in response to the earlier request, to

announce a new doctrine regarding the employment of the Armed Forces.167 Cushing’s response

went well beyond the question of whether the “bystanders” contemplated by the Fugitive Slave

Act might include members of a state militia when not in federal service, and announced a

broader principle—members of the military by virtue of their duties as citizens were part of the

posse comitatus. Apparently adopting the views expressed earlier by the Senate Judiciary

Committee in reaction to the previous Administration’s views on the matter, Cushing declared:

The posse comitatus comprises every person in the district or county above the age of

fifteen years, whatever may be their occupation, whether civilians or not; and including the

military of all denominations, militia, soldiers, marines, all of whom are alike bound to

obey the commands of the sheriff or marshal. The fact that they are organized as military

bodies, under the immediate command of their own officers, does not in any wise affect

their legal character. They are still the posse comitatus. (xxi Parl. Hist., p.672, 688, per

Lord Mansfield).168

regular military forces to enforce due execution of the laws would be rarely used, only after civil power (with the aid of

military units as a posse comitatus) were to prove inadequate. Id. at 1.

160 6 Op. Att’y Gen. 466, 466 (1854).

161 Id.

162 Id.

163 Id.

164 S. DOC. NO. 67-263, supra note 36, at 63.

165 Id. at 64.

166 Id. at 63-65 (recounting the “Anthony Burns” riots and a similar incident that occurred in Racine, Wisconsin in

1854).

167 See COAKLEY, supra note 58, at 133-137 (reporting that Cushing’s opinion was drafted in the midst of widespread

resistance in Boston to the rendition of Anthony Burns, which became the occasion for the largest military posse

comitatus ever assembled, albeit not under the effective direction of the marshal).

168 6 Op. Att’y Gen. 466, 473 (1854). Cushing’s citation to Lord Mansfield is apparently a reference to the remarks of

the English Chief Justice during debate in the House of Lords concerning the validity of use troops to quell rioters in

London:

Lord Mansfield ... went on: ‘....[I]t appears most clearly to me, that every man may legally interfere

to suppress a riot, much more to prevent acts of felony, treason, and rebellion, in his private

capacity, but he is bound to do it as an act of duty; and if called upon by a magistrate, is punishable

in case of refusal.... A private man, if he sees a person committing an unlawful act, ... may

apprehend the offender, and ... may use force to compel him, not to submit to him, but to the law.

What a private man may do, a magistrate or peace officer may clearly undertake; and according to

the necessity of the case ... , any number of men assembled or called together for the purpose are

justified to perform. This doctrine I take to be clear and indisputable, with all the possible

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Two years later, Cushing’s opinion supplied the justification for the use of federal troops at the

call of civil law enforcement authorities in what some saw as partisan involvement in the conflict

between pro- and anti-slavery forces in Kansas.169 Congress reacted with a rider to an Army

appropriations bill forbidding the use of any “part of the military forces of the United States to

enforce territorial law in Kansas.”170 After some discussion of whether the amendment was

germane, it was defeated.

consequences which can flow from it, and to be the true foundation for calling in of the military

power to assist in quelling the late riots.

The persons who assisted in the suppression of those riots and tumults, in contemplation of law, are

to be considered as mere private individuals, acting according to law, and upon any abuse of the

legal power with which they are invested, are amendable to the laws of their country.

... On the whole, my lords, while I ... sincerely lament the cause which rendered it indispensably

necessary to call out the military to assist in the suppression of the late disturbances, I am clearly of

the opinion, that no steps have been taken which were not strictly legal, as well as fully justifiable

in point of policy.... The military have been called in, ... not as soldiers, but as citizens: no matter

whether their coats be red or brown, they have been called in aid of the laws, not to subvert them,

or overturn the constitution, but to preserve both.”

XXI HANSARD, THE PARLIAMENTARY HISTORY OF ENGLAND FROM THE EARLIEST PERIOD TO THE YEAR 1803, at 690-98

(June 19, 1780). Cushing seemed to turn Lord Mansfield’s point on its head when he wrote that, “the fact that they are

organized as military bodies, under the immediate command of their own officers, does not in any wise affect their

legal character.” English law prohibited martial law, the use of military force domestically, in peacetime England. Lord

Mansfield justified an apparent breach of the martial law proscription by asserting that the soldiers had acted as

individuals called, commanded, and governed exclusively by the dictates of law applicable to civilians. Civilians are

not organized as military units and are not subject to the command of military officers. Lord Mansfield’s justification

could only hold as long as the soldiers were not organized as military bodies and were not acting under the command of

their officers. The fact that they were organized as military bodies, under the immediate command of their own

officers, was the critical determinant of their legal character.

169 President Pierce told Congress:

The Constitution requiring [the Executive] to take care that the laws of the United States be

faithfully executed, if they be opposed in the Territory of Kansas he may, and should, place at the

disposal of the marshal any public force of the United States which happens to be within the

jurisdiction, to be used as a portion of the posse comitatus ; and if that do not suffice to maintain

order, then he may call forth the militia of one or more States for that object, or employ for the

same object any part of the land or naval force of the United States. So, also, if the obstruction be to

the laws of the Territory, and it be duly presented to him as a case of insurrection, he may employ

for its suppression the militia of any State or the land or naval force of the United States.

V JAMES D. RICHARDSON, A COMPILATION OF THE MESSAGES AND PAPERS OF THE PRESIDENTS 358 (1897); see also

EDWARD CORWIN, THE PRESIDENT: OFFICE AND POWERS, 1787-1984, 155 (5th ed. 1984) (calling Cushing’s opinion an

ingenious means of virtually eliminating the proclamation requirement under the Insurrection Act by enabling marshals

to summon both state militia and U.S. regular forces within their precincts to assist in enforcing the law, noting

President Pierce’s use of new doctrine to declare it his duty to place U.S. forces in Kansas at the disposal of marshal).

170 By the proposed legislation, would Congress would have given itself final authority to select which of the

contending governments to recognize:

But Congress hereby disapproving the code of alleged laws officially communicated to them by

the President, and which are represented to have been enacted by a body claiming to be the

Territorial Legislature of Kansas; and also disapproving of the manner in which said alleged laws

have been enforced by the authorities of said Territory, expressly declare that, until those alleged

laws shall have been affirmed by the Senate and House of Representatives as having been enacted

by a legal Legislature, chosen in conformity with the organic law, by the people of Kansas, no part

of the military force of the United States shall be employed in aid of their enforcement, nor shall

any citizen of Kansas be required, under those provisions to act as a part of the posse comitatus of

any officer acting as a marshal or sheriff in said Territory.

CONG. GLOBE 34th Cong., 1st & 2d Sess. 1813 (1856).

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Passage of the Posse Comitatus Act

Following the Civil War, the use of federal troops to execute the laws, particularly in the states

that had been part of the Confederacy, continued even after all other political restrictions had been

lifted. By 1877, there was evidence that Republican state governments in more than one southern

state owed their continued political existence to the presence of the military and that the activities

of federal troops may have influenced the outcome of the Hayes-Tilden presidential election.171

The House of Representatives, controlled by a Democratic majority, passed an Army

appropriation bill which expressly prohibited use of the Army to shore up Republican state

governments in the South, or more precisely, to shore up either side of the political dispute in

Louisiana or anywhere else.172 The Senate, controlled by a Republican majority, refused to accept

the provision. No compromise could be reached, and the session ended without passage of an

Army appropriation bill. Money to pay the Army was subsequently appropriated in a special

session,173 without reference to restrictions on use of the Army.174 But when the issue of Army

appropriations next arose, the House included a posse comitatus section.175 The Senate accepted

the House version with minor amendments.176

171 Members of the two political parties understandably disagreed as to whether the presence of federal troops in the

South tainted or insured the integrity of the political process; compare, “[O]ur Army, degraded from its high position of

the defenders of the country from foreign and domestic foes, has been used as a police; has taken possession of polls

and controlled elections; has been sent with fixed bayonets into the halls of State Legislatures in time of peace and

under the pretense of threatened outbreak; has been placed under the control of subordinate State officials, and, under

the instructions of the Attorney General, has been notified to obey the orders of deputy United States marshals, ‘general

and special,’ appointed in swarms to do dirty work in a presidential campaign,” 5 CONG. REC. 2117 (remarks of Rep.

Banning), with, “Nor do I think, sir, that the use of troops in the States recently in rebellion was uncalled for or

inconsistent with the spirit of republican liberty. If they were recalled before every man, white and black, was safe –

safe and truly free, with all his civil rights in their fullest extent – they were recalled too soon.” 7 CONG. REC. 3616

(remarks of Rep. Philips).

172 Section 5 of H.R. 4691, as passed by the House, provided, “That no part of the money appropriated by this act, nor

any money heretofore appropriated, shall be applied to the pay, subsistence, or transportation of troops used, employed,

or to be used or employed, in support of the claim[s of various individuals and bodies purporting to comprise the valid

government of Louisiana]; nor in the aid of the execution of any process in the hands of the United States marshal in

said State issued in aid of and for the support of any such claims. Nor shall the Army, or any portion of it, be used in

support of the claims, or pretended claim or claims, of any State government, or officer thereof, in any State, until the

same shall have been duly recognized by Congress. Any person offending against any of the provisions of this act shall

be guilty of a misdemeanor, and, upon conviction thereof, shall be imprisoned at hard labor for not less than five years

or more than ten years.” 5 CONG. REC. 2119 (1877).

173 See Presidential Proclamation of May 5, 1877, 20 Stat. 803 (1877) (calling Congress into session).

174 The bill contained no posse comitatus provisions because the President had withdrawn federal troops from

Louisiana and South Carolina and because of concern over disturbances on the Mexican border and over Indian

uprisings. 6 CONG. REC. 287 (remarks of Rep. Atkins) (1877).

175 “From and after the passage of this act it shall not be lawful to employ any part of the Army of the United States as a

posse comitatus or otherwise under the pretext or for the purpose of executing the laws, except in such cases and under

such circumstances as such employment of said forces may be expressly authorized by act of Congress; and no money

appropriated by this act shall be used to pay any of the expenses incurred in the employment of any troops in violation

of this section; and any person violating the provisions of the this section shall be deemed guilty of a misdemeanor, and

on conviction thereof shall be punished by a fine not exceeding $10,000 or imprisonment not exceeding two years, or

both such fine and imprisonment.” 7 CONG. REC. 3845 (1878).

176 The “pretext” language was stricken because it was thought to be “in the nature of a reflection upon the past

administration of the Government.” 7 CONG. REC. 4648 (remarks of Sen. Sargent). Instances of express Constitutional

authority were added to the statutory exception, although then as now the precise effect of this change was a matter of

dispute; the penalty was applicable only to willful violations, although a Senate requirement that the penalty be

restricted to willful and knowing violations was not accepted. Id.

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At least one contemporary military jurist viewed the new law as having less than a momentous

impact on the relationship between civil and military authorities.177 Colonel William Winthrop

opined that, the occasion for its enactment having passed, the act remained “a mere impediment

to the constitutional exercise of the executive power of the nation.”178 While federal marshals

could no longer avail themselves of military assistance to arrest individuals charged with offenses

against the United States, he stressed that wherever a combination existed to resist the

enforcement of the laws, the President always could invoke the Insurrection Act.179 He further

made note of the already sizable list of exceptions to the prohibition.180

Others have viewed the act as having a deleterious effect on the nation’s commitment to civilian

law enforcement. While soldiers serving on a posse remained subordinate to civilian rules and

law enforcement officers, troops called out under the Insurrection Act came to be viewed as an

independent military force enforcing something like martial law, if not engaging in all-out war.181

Today, however, the act is widely regarded as the embodiment of the American tradition of antimilitarism.182

Despite early efforts on the part of the executive branch to get the provision repealed or

amended,183 the Posse Comitatus Act has remained essentially unchanged since its passage.184

177 See WINTHROP, supra note 150, at 867.

178 Id.

179 See id.

180 Id.

181 See Engdahl, supra note 10, at 62-64 (“By the end of the [19th] century it had become thoroughly established in the

common understanding that wherever and whenever military troops were employed, it was equivalent to war.”).

182 Cf Felicetti & Luce, supra note 141, at 91 (arguing that “courts analyzing the Act [have written] about the law as if

it was the only law or principle that limited the use of the armed forces in a law enforcement role. Some, therefore,

have claimed to discern a broader policy or ‘spirit’ behind the Act that is not supported by the historical record or the

statute’s text. While these wider policies are sound, they are embodied in federalism, the law concerning federal arrest

authority, election law, and especially fiscal law. The ... Posse Comitatus Act ... doesn’t have to do all the work, a view

that even the Act’s original proponents appeared to recognize. Trying to force-fit all these other principles into the

surviving part of the Act has only created a need to ‘discover’ a number of implied exceptions and has sowed a great

deal of confusion.”); C.J. Williams, An Argument for Putting the Posse Comitatus Act to Rest, 85 MISS. L.J. 99, 164-65

(2016) (“As a symbolic expression of the traditional American value of maintaining civilian control of the military, the

Posse Comitatus Act fails. The Act imposes criminal sanctions on civilian authorities that use the military to enforce

laws, rather than limit criminal sanctions to military authorities that usurp civilian control. As a practical tool to

effectuate lofty means of maintaining a separation between the military and civilian law enforcement, it likewise fails.

Its vague language has caused nothing but confusion and motivated Congress to enact so many exceptions to the Act

that it has long since been swallowed.”).

183 See Rutherford B. Hayes, Second Annual Message to Congress, 8 CONG. REC. 5 (1878) (noting recommendation of

the Secretary of War that the provision be repealed or amended); 1 Annual Report of the Secretary of War for 1878, at

VI-VII (advising repeal of posse comitatus provision or expansion of exceptions to permit employment of the Army to

counter lawlessness in Arizona territory); see also Chester A. Arthur, First Annual Message to Congress, 13 CONG.

REC. 28 (1881) (advising an exception permitting the military to assist the civil Territorial authorities in enforcing the

laws of the United States); Chester A. Arthur, Special Message, 13 CONG. REC. 3355 (1882) (same). Congress declined

to exempt the territories at that time, apparently due to the belief that sufficient authority existed in insurrection statutes

to permit military intervention to execute federal law, albeit under presidential authority rather than that of the federal

marshal. See 13 CONG. REC. 3457-58 (1882) (statement by Senator Edmunds, reporting conclusion of the Senate

Judiciary Committee). In 1900, however, Congress enacted an exemption for the District of Alaska, Act of June 6,

1900, 31 Stat. 330.

184 For some time the act was contained in Title 10 of the United States Code and expressly exempted the territory of

Alaska, 10 U.S.C. § 15 (1940 ed.). When Title 10 was recodified and the section transferred to Title 18, the Air Force,

previously covered while it was part of the Army, was expressly added to the act, and the reference to Alaska, by then a

state, disappeared. 70A Stat. 626 (1956).

Over the years, Congress has adjusted the impact of the Posse Comitatus Act by enlarging the number of statutes which

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Congress has, however, authorized a substantial number of exceptions and has buttressed the act

with an additional proscription against use of the Armed Forces to make arrests or conduct

searches and seizures.185

Constitutional Considerations

The Posse Comitatus Act raises at least three constitutional questions: (1) To what extent does the

Posse Comitatus Act track constitutional requirements, beyond the power of the President or

Congress to adjust or ignore? (2) To what extent do the powers which the Constitution vests in the

President limit the power of Congress to enact the Posse Comitatus Act or any other provision

restricting the President’s discretion to involve the Armed Forces in civilian affairs? (3) What

specifically are the military law enforcement activities “expressly authorized in the Constitution”

for purposes of the act?

Constitutional Origins

Lord Coke and his colleagues, in crafting the Petition of Right of 1628, found within that chapter

of the Magna Carta and subsequent explanatory statutes that are the antecedents of our

constitutional due process clauses a prohibition against martial law.186 In times of peace, this

proscription would not abide either the quartering of troops among civilians or any form of

martial law, be it imposed by tribunal or more summarily dispatched by soldiers controlling or

punishing civilians.

The Declaration of Independence lists the imposition of martial law upon us among those affronts

to fundamental liberties that irrevocably ruptured our political ties to Great Britain.

Finally, it is possible to see the protrusions of a larger, submerged constitutional principle which

bars the use of the Armed Forces to solve civilian inconveniences in the Second, Third, and Fifth

Amendments, with their promises of a civilian militia, freedom from the quartering of troops

among us, and the benefits of due process.

This view is not without judicial support. The courts have demonstrated a rather long-standing

reluctance to recognize the authority of military tribunals over civilians.187 And members of the

expressly authorize the use of the Army or Air Force to execute the law. These are sometimes referred to as

“amendments” to the Posse Comitatus Act. Since they do not change language of the act itself, it seems to be more

accurate to characterize them as expansions of authority under the statutory exception to the Posse Comitatus Act rather

than as amendments or changes in the act itself.

185 “The Secretary of Defense shall prescribe such regulations as may be necessary to ensure that any activity

(including the provision of any equipment or facility or the assignment or detail of any personnel) under this chapter

[10 U.S.C. §§ 271-282] does not include or permit direct participation by a member of the Army, Navy, Air Force, or

Marine Corps in a search, seizure, arrest, or other similar activity unless participation in such activity by such member

is otherwise authorized by law.” 10 U.S.C. § 275.

Soon after the enactment of current § 275, the Secretary of Defense promulgated such regulations which, subject to

designated exceptions, prohibited: “(i) Interdiction of a vehicle, vessel, aircraft or other similar activity. (ii) A search or

seizure, (iii) An arrest, stop and frisk, or similar activity. (iv) Use of military personnel for surveillance or pursuit of

individuals, or as informants, undercover agents, investigators, or interrogators.” 32 C.F.R. § 213(10)(a)(3), 47 Fed.

Reg. 14899, 14902 (April 7, 1982). Some years later the regulations were removed, 53 Fed. Reg. 23776 (April 28,

1993) and replaced with a new regulation combining various authorities related to domestic operations, 32 C.F.R. Part

185, 58 Fed. Reg. 52667 (Oct. 12, 1993), which in turn referred to relevant DOD Directives setting forth regulations in

greater detail.

186 See supra “Background.”

187 Ex parte Milligan, 71 U.S. (4 Wall.) 3, 123-25 (1866); Toth v. Quarles, 350 U.S. 11 (1955); Reid v. Covert, 354

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Supreme Court seemed to acknowledge possible components of a larger principle in both

Youngstown Sheet and Tube Co. v. Sawyer188 and Laird v. Tatum.189

But if a larger anti-martial law principle lies beneath constitutional sands, visible only in these

amendments and the spirit of the Posse Comitatus Act, it has remained remarkably dormant.

Those regions from which it might have been expected to emerge have been characterized most

by inactivity. The boundaries of the Third Amendment are virtually uncharted.190 Until recently,

U.S. 1 (1957); Kinsella v. Singleton, 361 U.S. 234 (1960); Grisham v. Hagan, 361 U.S. 278 (1960); McElroy v.

Guagliardo, 361 U.S. 281 (1960); O’Callahan v. Parker, 395 U.S. 258 (1969); but see Solorio v. United States, 483

U.S. 435 (1987) (holding that the jurisdiction of military tribunals depends upon whether the accused was a member of

the Armed Forces at the time of alleged misconduct and, contrary to O’Callahan, not whether the crime was “service

connected”).

188 343 U.S. 579 (1952).

Article II, Section 2 make the Chief Executive the Commander in Chief of the Army and Navy. But

our history and tradition rebel at the thought that the grant of military power carries with it

authority over civilian affairs.

343 U.S. at 632 (Douglas, J., concurring).

Time out of mind, and even now in many parts of the world, a military commander can seize

private housing to shelter his troops. Not so, however, in the United States, for the Third

Amendment says, ‘No Soldier shall, in time of peace be quartered in any house, without the

consent of the Owner, nor in time of war, but in a manner to be prescribed by law.’ Thus, even in

war time, his seizure of needed military housing must be authorized by Congress. It also was

expressly left to Congress to ‘provide for calling forth the Militia to execute the laws of the Union,

suppress Insurrections and repel Invasions....” Such a limitation on the command power, written at

a time when the militia rather than a standing army was contemplated as the military weapon of the

Republic, underscores the Constitution’s policy that Congress, not the Executive, should control

utilization of the war power as an instrument of domestic policy. Congress, fulfilling that function,

has authorized the President to use the army to enforce certain civil rights. On the other hand,

Congress has forbidden him to use the army for the purpose executing general laws except when

expressly authorized by the Constitution or Act of Congress.

343 U.S. at 644-45 (Jackson, J., concurring) (emphasis in the original).

In Youngstown, the Court held that, when Congress had specifically refused to grant such authority by statute, the

President’s constitutional and statutory powers as President and Commander in Chief were not sufficient to support an

executive order authorizing the Secretary of Commerce to use the resources of the federal government, including its

Armed Forces, to seize and operate the country’s steel mills which were then threatened by a nation-wide strike. Id. at

587.

189 408 U.S. 1 (1972).

The concerns of the Executive and Legislative Branches in response to disclosure of the Army

surveillance activities – and indeed the claims alleged in the complaint – reflect a traditional and

strong resistance of Americans to any military intrusion into civilian affairs. That tradition has deep

roots in our history and found early expression, for example, in the Third Amendment’s explicit

prohibition against quartering soldiers in private homes without consent and in the constitutional

provisions for civilian control of the military. Those prohibitions are not directly presented by this

case, but their philosophical underpinnings explain our traditional insistence on limitations on

military operations in peacetime.

Id. at 15-6.

In Laird v. Tatum, the Court refused to order the military to stop collecting information about civilians unless the

civilians could show how they had been hurt by what the military was doing. Id. at 3. (More precisely the Court held

that, in the absence of any showing of specific harm or the realistic threat of specific harm, a claim, that the data

gathering activities of the military services had been conducted so as to chill the First Amendment rights of the targets

of those intelligence collection efforts, was nonjusticiable.)

190 See Tom W. Bell, The Third Amendment, Forgotten But Not Gone, 2 WM & MARY BILL RTS. J. 117 (1993); William

S. Fields and David T. Hardy, The Third Amendment and the Issue of the Maintenance of Standing Armies: A Legal

History, 35 AM. J. LEGAL HIST. 393 (1991); William Sutton Fields, The Third Amendment: Constitutional Protection

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the outreaches of the militia-related Second Amendment appeared only slightly more visible.191

Even in the inviting context of the Posse Comitatus Act, the courts have generally avoided

excursions into areas of its possible constitutional underpinnings.192

On the other hand, the Constitution appears to recognize that military force might occasionally be

called for in handling domestic affairs. It permits Congress to authorize the use of the militia “to

execute the Laws of the Union, suppress Insurrections and repel Invasions.”193 And it guarantees

the states protection against invasion or usurpation of their “republican form of government,”

and, upon the request of the state legislature, against “domestic violence.”194 While states are

prohibited from keeping their own standing armies,195 they retain some control over their militias,

subject to any constraints Congress may constitutionally impose, including the authority to call

forth those forces to suppress insurrections or quell civil disturbances.196 The Constitution neither

authorizes nor proscribes martial law (which is said to exist when civil authority is supplanted by

From the Involuntary Quartering of Soldiers, 124 MIL. L. REV. 195 (1989). In one of the few reported Third

Amendment cases, striking state correctional officers brought a civil rights action against state authorities who had used

the officers’ prison facility resident quarters to house replacement national guard troops. The district court dismissed,

Engblom v. Carey, 522 F. Supp. 57, 70 (S.D.N.Y. 1981), the appellate court reversed on the ground that it could not

hold as a matter of law that the officers had no Third Amendment possessory interest in the resident quarters, 677 F.2d

957, 964 (2d Cir. 1982). On remand the district court dismissed based on the qualified immunity of the defendant state

officials in light of the uncertainty of the right with respect to Third Amendment questions, 572 F. Supp. 44, 49

(S.D.N.Y.), aff’d, 724 F.2d 28 (2d Cir. 1983). The implications of the case prior to remand are discussed in The Third

Amendment’s Protection Against Unwanted Military Intrusions, 49 BROOK. L. REV. 857 (1983).

191The Second Amendment might be seen as evidence of the founders’ preference for the Minute Men over Hessian

mercenaries as a means of common defense. Story, speaking of the Second Amendment, noted the distaste in the early

Republic not simply for a standing army’s involvement in domestic affairs but for existence of a standing army at all:

The militia is the natural defence of a free country against sudden foreign invasions, domestic

insurrections, and domestic usurpations of power by rulers. It is against sound policy for a free

people to keep up large military establishments and standing armies in time of peace, both from the

enormous expenses, with which they are attended, and the facile means, which they afford to

ambitious and unprincipled rulers, to subvert the government, or trample upon the rights of the

people. The right o f the citizens to keep and bear arms has justly been considered, as the palladium

of the Liberties of a republic; since it offers a strong moral check against the usurpation and

arbitrary power of rulers; and will generally, even if these are successful the first instance, enable

the people to resist and triumph over them.

III JOSEPH STORY, COMMENTARIES ON THE CONSTITUTION OF THE UNITED STATES § 1890 (1833). At one time, scholars

disagreed over whether the Second Amendment’s predominant theme is the right to bear arms or this perceived need

for a well regulated militia. See William Van Alstyne, The Second Amendment and the Personal Right to Bear Arms,

43 DUKE L. J. 1236 (1994); Andrew D. Herz, Gun Crazy: Constitutional False Consciousness and Dereliction of

Dialogic Responsibility, 75 B.U. L. REV. 57 (1995). The Supreme Court seems to have resolved the matter in favor of

the former. District of Columbia v. Heller, 554 U.S. 570 (2008).

192 See, e.g., United States v. Walden, 490 F.2d 372, 376 (4th Cir. 1974) (“[W]e do not find it necessary to interpret

relatively unexplored sections of the Constitution in order to determine whether there might be constitutional objection

to the use of the military to enforce civilian laws”).

193 U.S. CONST. art I, § 8, cl. 15.

194 U.S. CONST. art IV, § 4.

195 U.S. CONST. art. I, § 10, cl.3.

196 See Luther v. Borden, 48 U.S. (7 How.) 1, 45 (1849) (“[U]nquestionably a State may use its military power to put

down an armed insurrection too strong to be controlled by the civil authority.”).

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military rule due to war or similar emergency),197 but it has been proclaimed on rare occasions.198

Lesser forms of military involvement in law enforcement have not been commonplace, but have

not been particularly rare during the history of the republic.

Without more judicial guidance, it would appear that traditional reservations about military

involvement in the execution of civilian law can only clearly be said to rise to the level of

constitutional imperative when they take a form that offends some more explicit constitutional

prohibition or guarantee such as the right to jury trial, grand jury indictment, or freedom from

unreasonable searches and seizures.199 Consequently, beyond those specific constitutional

provisions, Congress’s constitutional authority to enact and adjust the provisions of the Posse

Comitatus Act is largely a matter of the coordination of congressional and presidential powers.

Presidential vs. Congressional Powers

The case of conflicting congressional and presidential powers is easily stated if not easily

resolved. On one hand, the Constitution requires the President to take care to see that the laws are

faithfully executed, and designates him as Chief Executive and Commander in Chief of the

Armed Forces.200 In this dual capacity, the presidency is the repository of both extensive

responsibilities and broad prerogatives, not the least of which flow from Article IV, Section 4 of

the Constitution, which guarantees the states a republican form of government and protection

against invasion and domestic violence.201

197 See, e.g., GEORGE B. DAVIS, A TREATISE OF THE MILITARY LAW OF THE UNITED STATES 300 (3d ed. 1913)

(describing “martial law” as a term applied to the “temporary government, by military authority, of a place or district in

which, by reason of the existence civil disorder, or a state of war and the pendency of military operations, the civil

government is, for the time being, unable to exercise its functions.”)

198 See Jason Collins Weida, Note, A Republic of Emergencies: Martial Law in American Jurisprudence, 36 CONN. L.

REV. 1397 (2004); Kirk L. Davies, The Imposition of Martial Law in the United States, 49 A.F. L. REV. 67, 111 (2000);

George M. Dennison, Martial Law: The Development of a Theory of Emergency Powers, 1776-1861, 18 AM. J. LEGAL

HIST. 52, 56-58 (1974). Until recently, federal regulation provided for martial law in certain circumstances. See former

32 C.F.R. Part 501 (2007). According to former 32 C.F.R. § 501.4:

When Federal Armed Forces are committed in the event of civil disturbances, their proper role is to

support, not supplant, civil authority. Martial law depends for its justification upon public

necessity. Necessity gives rise to its creation; necessity justifies its exercise; and necessity limits its

duration. The extent of the military force used and the actual measures taken, consequently, will

depend upon the actual threat to order and public safety which exists at the time.

The regulation went on to say that declarations of martial law are ordinarily made by the President, but that the decision

could be made “by the local commander on the spot, if the circumstances demand immediate action, and time and

available communications facilities do not permit obtaining prior approval from higher authority.” Id. The regulation

was withdrawn in 2008. 73 Fed. Reg. 23,350 (Apr. 30, 2008) (noting that the responsibility to prepare for civil

disturbances has been transferred to Office of the Assistant Secretary of Defense for Homeland Defense). Until 1993,

32 C.F.R. Part 185, Defense Support of Civil Defense, contained a provision authorizing senior military to impose

martial law where the President had not done so in the event of a complete breakdown of civil governance. The

regulation further stated that military resources could not be employed for law enforcement purposes unless martial law

had been proclaimed or a serious breakdown of law and order impelled civil authorities to request military assistance to

prevent loss of life or wanton destruction of property. 32 C.F.R. § 185.4 (1993).

199 See James P. O’Shaugnhessy, Note, The Posse Comitatus Act: Reconstruction Politics Reconsidered, 13 AM. CRIM.

L. REV. 703, 712-13 (1976).

200 U.S. CONST. art. II, § 1 (“[t]he executive Power shall be vested in a President of the United States of America”), § 2

(“[t]he President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the

several States, when called into actual Service of the United States”), § 3 (“[The President] shall take Care that the

Laws be faithfully executed”).

201 “The United States shall guarantee to every State in this Union, a Republican Form of Government, and shall protect

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The Supreme Court has made it clear that the President is not dependent upon express

constitutional or statutory authorization for the exercise of his powers. Thus, he may meet an

emergency by appointing a marshal to protect a threatened Supreme Court Justice, although no

statute expressly authorized appointment for such purposes.202 He must resist invasion by an

enemy with force though Congress has yet to declare war.203 And when an emergency arises

threatening the freedom of interstate commerce, transportation of the mails, or some other

responsibility entrusted to the federal government, he may call upon “the army of the Nation, and

all its militia ... to brush away the obstructions.”204

Some commentators feel that this implied or incidental constitutional authority to use the Armed

Forces not only exists in the absence of congressional direction, but is immune from

congressional direction or limitation.205

On the other hand, Congress shares constitutional power over the laws and Armed Forces with the

President. The Constitution gives Congress the power to make the laws whose faithful execution

the President must take care to observe and which carry into execution Congress’s own powers

and those of the President.206 It likewise vests Congress with the power to establish, maintain, and

regulate the Armed Forces;207 and with the power to describe the circumstances under which the

militia may be called into federal service.208

The Supreme Court has shed some light on the coordination of presidential and congressional

powers concerning use of the military to enforce civilian law. The Court has pointed out that the

President’s power under the Guarantee Clause of Article IV, Section 4, which guarantees the

states protection against domestic violence, is only provisionally effective until such time as

Congress acts.209 And the President may not always use the Armed Forces to meet a domestic

emergency when Congress has previously resisted an invitation to sanction their employment. 210

Finally, even when Congress has disclaimed any intent to limit the exercise of the President’s

constitutional powers, the President’s implied and incidental powers will not always trump

conflicting, constitutionally grounded claims.211

each of them against Invasion; and on Application of the Legislature, or of the Executive (when the Legislature cannot

be convened) against domestic Violence.” U.S. CONST. art. IV, § 4.

202 In re Neagle, 135 U.S. 1, 62-4 (1890).

203 The Prize Cases, 67 U.S. (2 Black) 635, 668 (1863).

204 In re Debs, 158 U.S. 364, 381 (1895).

205 See, e.g., Walter A. Lorence, The Constitutionality of the Posse Comitatus Act, 8 U. KAN. CITY L. REV. 164, 185-91

(1940); H.W.C. Furman, Restrictions Upon Use of the Army Imposed by the Posse Comitatus Act, 7 MIL. L. REV. 85,

91-2 (1960); CORWIN, supra note 169, at 152-61.

206 U.S. CONST. art. I, § 8, cl.18.

207 U.S. CONST. art. I, § 8, cls.12, 13, & 14.

208 U.S. CONST. art. I, § 8, cls.15 & 16.

209 See Texas v. White, 74 U.S. (7 Wall.) 700, 730 (1869).

210

See Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579 (1952). In Youngstown, President Truman attempted to

invoke his powers as Commander in Chief and Chief Executive to seize and operate most of the Nation’s steel mills

during the Korean conflict when it appeared they might be shut down by a labor dispute. Congress had earlier

specifically refused to grant the President such power legislatively. Id. at 586.

211 See United States v. United States District Court, 407 U.S. 297, 303 (1972). Congress had established a warrant

procedure to be used by law enforcement officials to permit wiretapping in criminal cases. In doing so, it expressly

disclaimed any intent to “limit the constitutional power of the President to take such measures as he deems necessary to

protect the Nation against actual or potential attack or other hostile acts of a foreign power, to obtain foreign

intelligence information deemed essential to the security of the United States, or to protect national security

information against foreign intelligence activities [or] to take such measures as he deems necessary to protect the

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Constitutional Exceptions

The Posse Comitatus Act does not apply “in cases and under circumstances expressly authorized

by the Constitution.”212 It has been said that the Constitution contains no provision expressly

authorizing the use of the military to execute the law in such a way,213 and that this reference to

constitutional exceptions was included as part of a face-saving compromise that consequently

should be ignored.214

When the phrase was added originally, those who opposed the Posse Comitatus Act believed that

the Constitution vested implied and/or inherent powers upon the President to use the Armed

Forces to execute the laws; those who urged its passage believed the President possessed no such

powers.215 As initially passed by the House, the bill contained no constitutional exception.216 The

Senate version contained an exception for instances authorized by the Constitution whether

expressed or otherwise.217 The managers of each house described the compromise reached at

United States against the overthrow of the Government by force or other unlawful means, or against any clear and

present danger to the structure or existence of the Government,” 18 U.S.C. § 2511(3) (1970). Even in the absence of

congressionally asserted counter authority, a unanimous Court declined to accept the argument that President’s inherent

and incidental constitutional powers permitted a failure to comply with the Fourth Amendment’s warrant requirements

when gathering intelligence concerning purely domestic threats to national security. Id. at 332.

212 18 U.S.C. § 1385 (2018).

213 H.R. REP. NO. 97-71, at 6 n.3, reprinted in 1981 U.S.C.C.A.N. at 1789 n.3 (“The statute permits Constitutional

exceptions. However, there are none”); G. NORMAN LIEBER, THE USE OF THE ARMY IN AID OF THE CIVIL POWER 17

(1898); John P. Coffey, Note, The Navy’s Role in Interdicting Narcotics Traffic: War on Drugs or Ambush of the

Constitution?, 75 GEO. L.J. 1947, 1951 (1987); John D. Gates, Note, Don’t Call Out the Marines: An Assessment of the

Posse Comitatus Act, 13 TEX. TECH. L. REV. 1467, 1486 (1982); O’Shaugnhessy, supra note footnote 199, at 712.

The Constitution does empower Congress “to provide for calling forth the Militia to execute the laws of the Union,

suppress insurrections and repel invasions,” U.S. CONST. art. I, § 8, cl. 15; but since this express grant of authority can

only be activated by an act of Congress, it adds nothing to the “act of Congress” exception also included within the

Posse Comitatus Act.

214 The act also provides that the Army and Air Force can be used on the basis of an express constitutional

authorization. This language reflects a compromise reached in the debate over the act. It is a meaningless proviso since

the Constitution does not expressly authorize such a use of troops.

In any event, if the Constitution provided the President with authority over a purely executive function, Congress could

not disable the President from acting on the basis of it, whether the authorization was express or implied. But since the

Constitution provides Congress with the power to control military intervention in domestic affairs, the President’s

actions can be limited to the express terms of a statutory authorization. Honored in the Breech: Presidential Authority

to Execute the Laws with Military Force, 83 YALE L. J. 130, 143-44 (1973). See also O’Shaugnhessy, supra note 199,

at 712-13.

215 Compare 7 CONG. REC. 3582 (statement of Rep. Kimmel) with 7 CONG. REC. 3851-52 (statement of Mr. Gardner).

216 7 CONG. REC. 3877 (1878). As introduced, the measure provided:

From and after the passage of this act it shall not be lawful to employ any part of the army of the

United Sates as a posse comitatus or otherwise under the pretext or for the purpose of executing the

laws, except in such cases and under such circumstances as such employment of said force may be

expressly authorized by act of Congress; and no money appropriated by this act shall be used to pay

any of the expenses incurred in the employment of any troops in violation of this section; and any

person violating the provisions of this section shall be deemed guilty of a misdemeanor, and on

conviction thereof shall be punished by a fine of not exceeding $10,000 or imprisoned not

exceeding two years, or by both such fine and imprisonment. (Emphasis added).

217 7 CONG. REC. 4303-304 (1878). The Senate version would have provided:

From and after the passage of this act it shall not be lawful to employ any part of the army of the

United Sates as a posse comitatus or otherwise for the purpose of executing the laws, except in such

cases and under such circumstances as such employment of said force may be authorized by the

Constitution or by act of Congress; and no money appropriated by this act shall be used to pay any

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conference and subsequently enacted as upholding the position of their respective bodies on the

issue. While the House manager believed that retention of the word “expressly” was important to

prevent the use of the Army wherever implied authority could be inferred,218 the Senate manager

suggested that the term could safely be kept in without affecting the President’s ability to act as

required by the Constitution.219

Early commentaries suggest that the word “expressly” must be ignored, for otherwise in their

view the Posse Comitatus Act is a constitutionally impermissible effort to limit the implied or

inherent powers of the President.220 The regulations covering the use of the Armed Forces during

of the expenses incurred in the employment of any troops in violation of this section. (Emphasis

added).

218 As the House manager viewed the matter:

But these [compromises on other differences in the Army appropriation bill] are all minor points

and insignificant questions compared with the great principle which was incorporated by the House

in the bill in reference to the use of the Army in time of peace. The Senate had already conceded

what they called and what we might accept as principle; but they had stricken out the penalty and

had stricken out the word ‘expressly,’ so that the Army might be used in all cases where implied

authority might be inferred. The House committee planted themselves firmly upon the doctrine that

rather than yield this fundamental principle, for which for three years this House had struggled,

they would allow the bill to fail—notwithstanding the reforms which we had secured; regarding

these reforms as of but little consequence alongside the great principle in all its length and breadth,

including the penalty which the Senate had stricken out….We bring you back, therefore, a report

with the alteration of a single word, which the lawyers assure me is proper to be made, restoring to

this bill the principle for which we have contended so long, and which is so vital to secure the

rights and liberties of the people.

7 CONG. REC. 4686 (1878) (remarks of Rep. Hewitt).

219 The manager in the Senate described the compromise as follows:

With reference to the provisions of the bill inserted by the House prohibiting the use of the Army,

... Senators will remember that it was amended in the senate so as to strike out [‘pretext’ and

‘expressly,’ and the penalty, and amended] so as to read ‘by the Constitution or by act of

congress.’... We found considerable difficulty in agreeing upon this section, but the modification

which the Senate had made in it made it possible to come to an understanding.... As it now stands,

the House yielded that the words ‘under the pretext of’ should go out, which we contended were in

the nature of a reflection upon the past administration of the government, and we could not consent

that anything in the nature of a reflection, and which was entirely useless for any practical purpose,

should remain in the bill....

With reference to the word ‘expressly.’ we restored it and allowed it to go in, so that now the

employment of such force must be expressly authorized by the Constitution or by act of Congress,

they assenting that the words ‘the Constitution or by’ before the words ‘act of Congress’ might

remain in, so that if the power arises under either the Constitution or the laws it may be exercised

and the Executive would not be embarrassed by the prohibition of Congress so to act where the

Constitution requires him to act; and the embarrassments would not have the effect of restraining

the action of an upright and energetic Executive, but still might raise a question which he would

desire to avoid if possible....

7 CONG. REC. 4648 (1878) (remarks of Sen. Sargent).

220

See LIEBER, supra note 213, at 14-15.

The debate [on the Posse Comitatus section] was an interesting one, but too long to follow in detail.

An attempt was made to strike out the word “expressly,” but that failed. But, manifestly, the clause,

as enacted, recognizes the Constitution as a direct source of authority for the employment of the

Army. This is a very important consideration in the construction of the legislation. And another

matter of great importance is also to be observed with reference to it. The enactment prescribes that

it shall be unlawful to employ any part of the Army as a posse comitatus, or otherwise, for the

purpose of executing the laws, except when it is expressly authorized by the Constitution or by act

of Congress. Now, it is evident that the word ‘expressly’ can not be construed as placing a

restriction on any constitutional power. If authority so to use the Army is included in a

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civil disturbances do not go quite that far, but they do assert two constitutionally based

exceptions—sudden emergencies and protection of federal property.221

The question of whether the constitutional exception contained in the Posse Comitatus Act

includes instances where the President is acting under implied or inherent constitutional powers

or whether it was merely a face-saving device is a question that may turn on whether Congress

may constitutionally restrict the President’s powers, if any, in the area—a question the courts

have yet to answer.

When the Posse Comitatus Act Does Not Apply

In addition to any express constitutional exceptions, the use of the Armed Forces to execute

federal law does not violate the Posse Comitatus Act when (1) an act of Congress expressly

authorizes use of part of the Army or Air Force as a posse comitatus or otherwise to execute the

law; (2) the activity in question does not involve use of part of the Armed Forces covered by the

proscription; or (3) the activity in question does not constitute “execution of the law.”

constitutional power, although it be not expressly named, it can not, of course, be taken away by

legislation.

Lorence, supra note 205, at 185-86.

But it is evident that the word expressly in the Posse Comitatus Act cannot be construed as placing

a restriction on the constitutional Power of the President, because even though not expressly

named, such constitutional power cannot be taken away by legislation.... Thus, the Posse Comitatus

Act appears to be a rather singular statute to pass, saying that the Army of the United States shall

not be used for the purpose of executing the laws, in view of the fact that the Constitution expressly

makes the President the Commander-in-Chief of the Army and Navy, and expressly makes it his

duty to take care that the laws are faithfully executed.

221 According to 32 C.F.R. § 215.4(b),(c)(1),

(b) Aside from the constitutional limitations of the power of the Federal Government at the local

level, there are additional legal limits upon the use of military forces within the United States. The

most important of these from a civil disturbance standpoint is the Posse Comitatus Act (18 U.S.C.

§ 1385), which prohibits the use of any part of the Army or the Air Force to execute or enforce the

laws, except as authorized by the Constitution or Act of Congress.

(c) The Constitution and Acts of Congress establish six exceptions generally applicable within the

entire territory of the United States, to which the Posse Comitatus Act prohibition does not apply.

(1) The constitutional exceptions are two in number and are based upon the inherent legal right of

the U.S. Government – a sovereign national entity under the Federal Constitution – to insure the

preservation of public order and the carrying out of governmental operations within its territorial

limits, by force if necessary.

(i) The emergency authority. Authori[z]es prompt and vigorous Federal action, including use of

military force to prevent loss of life or wanton destruction of property and to restore governmental

functioning and public order when sudden and unexpected civil disturbances, disasters, or

calamities seriously endanger life and property and disrupt normal governmental functions to such

an extent that duly constituted local authorities are unable to control the situation.

(ii) Protection of Federal property and functions. Authorizes Federal action, including the use of

military forces, to protect Federal property and Federal governmental functions when the need for

protection exists and duly constituted local authorities are unable or decline to provide adequate

protection.

For a discussion of instances when the emergency, “immediate response authority” has been used, see Jim Winthrop,

The Oklahoma City Bombing: Immediate Response Authority and Other Military Assistance to Civil Authority

(MACA), 1997-JUL ARMY LAW. 3 (1997).

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Statutory Exceptions

Generally

The Posse Comitatus Act does not apply where Congress has expressly authorized use of the

military to execute the law.222 Congress has done so in three ways: (1) by giving a branch of the

Armed Forces civilian law enforcement authority; (2) by establishing general rules for certain

types of assistance; and (3) by addressing individual cases and circumstances with more narrowly

crafted legislation. Thus it has vested the Coast Guard, a branch of the Armed Forces, with broad

law enforcement responsibilities.223 Second, over time it has enacted a fairly extensive array of

particularized statutes, like those authorizing the President to call out the Armed Forces in times

of insurrection and domestic violence.224 Finally, it has passed general legislation permitting the

222 “Whoever, except in cases and under circumstances expressly authorized by the Constitution or Act of Congress,

willfully uses any part of the Army or the Air Force as a posse comitatus or otherwise to execute the laws shall be fined

under this title or imprisoned not more than two years, or both.” 18 U.S.C. § 1385 (2018) (emphasis added).

223 14 U.S.C. Section 2 provides:

The Coast Guard shall enforce or assist in the enforcement of all applicable Federal laws on, under,

and over the high seas and waters subject to the jurisdiction of the United states; shall engage in

maritime air surveillance or interdiction to enforce or assist in the enforcement of the laws of the

United States; shall administer laws and promulgate and enforce regulations for the promotion of

safety of life and property on and under the high seas and waters subject to the jurisdiction of the

United States covering all matters not specifically delegated by law to some other executive

department; shall develop, establish, maintain and operate with due regard to the requirements of

national defense, aids to maritime navigation, icebreaking facilities, and rescue facilities for the

promotion of safety on, under, and over the high seas and waters subject to the jurisdiction of the

United States; shall, pursuant to international agreements, develop, establish, maintain, and operate

icebreaking facilities on, under, and over the waters other than the high seas and waters subject to

the jurisdiction of the United States; shall engage in oceanographic research on the high seas and in

waters subject to the jurisdiction of the United States; and shall maintain a state of readiness to

function as a specialized service in the Navy in time of war, including the fulfillment of Maritime

Defense Zone command responsibilities.

Coast Guard personnel are also considered customs officers for purpose of customs law enforcement, 19 U.S.C.

§ 1401(i) ( 2018) (“When used in this subtitle [relating to administrative provisions concerning customs duties] or in

part I of subtitle II of this chapter [relating to the miscellaneous provisions of the Tariff Act of 1930] ... (i) The terms

‘officer of the customs’ and ‘customs officer’ mean ... any commissioned, warrant, or petty officer of the Coast Guard

... ”); 19 U.S.C. § 1709(b) (2018) (Coast Guard officers are customs officials for purposes of the Anti-Smuggling Act).

The Coast Guard has explicit law enforcement powers under 14 U.S.C. § 89 (2018) (“The Coast Guard may make

inquiries, examinations, inspections, searches, seizures, and arrests upon the high seas and waters over which the

United States has jurisdiction, for the prevention, detection, and suppression of violations of laws of the United

States.”); 14 U.S.C. § 91 (2018) (empowering Secretary of the respective department in which the Coast Guard is

operating to provide for safety and security of U.S. naval vessels). See generally Greg Shelton, Note, The United States

Coast Guard’s Law Enforcement Authority Under 14 U.S.C. § 89: Smugglers’ Blues or Boaters’ Nightmare?, 34 WM.

& MARY L. REV. 933 (1993); Christopher A. Abel, Note, Not Fit for Sea Duty: The Posse Comitatus Act, the United

States Navy, and Federal Law Enforcement at Sea, 31 WM. & MARY L. REV. 445 (1990).

224

Statutory exceptions to the Posse Comitatus Act include:

5 U.S.C. App. (Inspector General Act of 1978) § 8(g) (Department of Defense Inspector General is not limited by the

Posse Comitatus Act (18 U.S.C. § 1385) in carrying out audits and investigations under the act);

10 U.S.C. §§ 251-255 (President may use the militia and Armed Forces to suppress insurrection and enforce federal

authority in the face of rebellion or other forms of domestic violence);

10 U.S.C. § 12406 (President may call National Guard units or members into federal service to repel an invasion,

suppress a rebellion, or execute federal laws when he is unable to execute them using the regular forces);

16 U.S.C. § 23 (Secretary of the Army may detail troops to protect Yellowstone National Park upon the request of the

Secretary of the Interior);

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Armed Forces to share information and equipment with civilian law enforcement agencies,

subject to restrictions on engaging in direct and active law enforcement.225

16 U.S.C. § 78 (Secretary of the Army may detail troops to protect Sequoia and Yosemite National Parks upon the

request of the Secretary of the Interior);

16 U.S.C. § 593 (President may use the land and naval forces of the United States to prevent destruction of federal

timber in Florida);

16 U.S.C. § 1861(a) (Secretary of Homeland Security (or the Secretary of the Navy in time of war) may enter into

agreements for the use of personnel and resources of other federal or state agencies—including those of the Department

of Defense—for the enforcement of the Magnuson Fishery Conservation and Management Act);

18 U.S.C. §§ 112, 1116 (Attorney General may request the assistance of federal or state agencies—including the Army,

Navy and Air Force—to protect foreign dignitaries from assault, manslaughter and murder);

18 U.S.C. § 351 (FBI may request the assistance of any federal or state agency—including the Army, Navy and Air

Force—in its investigations of the assassination, kidnapping or assault of a Member of Congress);

18 U.S.C. § 1201 (Attorney General may request assistance from any Federal, State, or local agency, including the

Army, Navy, and Air Force, to enforce prohibition against kidnapping foreign officials and internationally protected

persons);

18 U.S.C. § 1751 (FBI may request the assistance of any federal or state agency—including the Army, Navy and Air

Force—in its investigations of the assassination, kidnapping or assault of the President);

18 U.S.C. § 3056 note (Director of the Secret Service may request assistance from the Department of Defense and other

federal agencies to protect the President);

18 U.S.C. § 3192 (President may employ such portion of the land or naval forces of the United States, or of the militia

thereof, as may be necessary for the safe-keeping and protection of an accused who is extradited to the United States);

22 U.S.C. § 408 (President may use the land and naval forces of the United States to enforce Title IV of the Espionage

Act of 1917 (arms embargoes) (22 U.S.C. §§ 401-408));

22 U.S.C. § 461 (President may use the land and naval forces and militia of the United States to enforce parts of the

Neutrality Act, 22 U.S.C. §§ 461-465 and 18 U.S.C. §§ 958-962);

22 U.S.C. § 462 (President may use the land and naval forces and militia of the United States to detain or compel

departure of foreign ships under the provisions of the Neutrality Act);

25 U.S.C. § 180 (President may use military force to remove trespassers from Indian treaty lands);

42 U.S.C. § 97 (“officers of the United States shall faithfully aid in the execution of [state] quarantines and health laws,

according to their respective powers and within their respective precincts, and as they shall be directed, from time to

time, by the Secretary of Health and Human Services”);

42 U.S.C. § 1989 (magistrates issuing arrest warrants for civil rights violations may authorize those serving the

warrants to call for assistance from bystanders, the posse comitatus, or the land or naval forces or militia of the United

States);

42 U.S.C. § 5170b (Governor of state in which a major disaster has occurred may request the President to direct the

Secretary of Defense to permit the use of DOD personnel for emergency work necessary for the preservation of life and

property, but DOD does not consider this provision to authorize law enforcement measures);

43 U.S.C. § 1065 (President may use military force to remove unlawful enclosures from the public lands);

48 U.S.C. § 1418 (President may use the land and naval forces of the United States to protect the rights of owners in

guano islands);

48 U.S.C. § 1422 (Governor of Guam may request assistance of senior military or naval commander of the Armed

Forces of the United States in cases of disaster, invasion, insurrection, rebellion or imminent danger thereof, or lawless

violence);

48 U.S.C. § 1591 (Governor of the Virgin Islands may request assistance of senior military or naval commander of the

Armed Forces of the United States in the Virgin Islands or Puerto Rico in cases of disaster, invasion, insurrection,

rebellion or imminent danger thereof, or of lawless violence);

49 U.S.C. § 324 (Secretary of Transportation may provide for participation of military personnel in carrying out duties);

50 U.S.C. § 220 (President may use the Army, Navy or militia to prevent the unlawful removal of vessels or cargoes

from customs areas during times of insurrection).

225 Military assistance available to civilian law enforcement entitles includes the following provisions:

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How explicit must a statutory exception be? If one believes the word “expressly” should be

ignored with respect to the constitutionally based exception, consistency might suggest no more is

required than that Congress authorize a thing to be done. To those so inclined, the position is

further fortified when the statute authorizes executive branch action in circumstances where the

President’s faithful execution responsibility,226 coupled with the Administrative Housekeeping

Statute,227 can be called into play. In this rarely espoused view, if an agency has statutory

authority to perform a task, the military may be asked to help.

Others maintain that statutes which authorize assistance from federal agencies and departments

generally in order to accomplish a particular task qualify as exceptions even if they do not

mention the Department of Defense or any part of the military establishment by name. 228 On the

one hand, such legislation has ordinarily come into being after the Posse Comitatus Act and thus

would ordinarily be thought to amend any conflicting earlier law. On the other hand, the use of

military force in civilian affairs is such an extraordinary thing that perhaps it ought not be

presumed, but rather found only where Congress has so stated in hoc verba.

10 U.S.C. § 271 (Secretary of Defense may provide federal, state, or local civilian law enforcement officials with

information collected during military training operations or training);

10 U.S.C. § 272 (Secretary of Defense may make equipment and facilities available to federal, state, and local law

enforcement operations);

10 U.S.C. § 273 (Secretary of Defense may train federal, state, and local law enforcement officials to operate and

maintain equipment);

10 U.S.C. § 274 (Secretary of Defense may provide personnel to maintain and operate equipment and facilities in

support of certain federal, state and local law enforcement operations;)

10 U.S.C. § 282 (the Secretary of Defense may provide assistance to the Department of Justice in emergency situations

involving chemical or biological weapons of mass destruction);

10 U.S.C. § 282 note (§ 1023 of the National Defense Authorization Act for Fiscal Year 2000) (during fiscal years 2000

through 2004, the Secretary of Defense was authorized to provide assistance to federal and state law enforcement

agencies to respond to terrorism or threats of terrorism);

10 U.S.C. § 283 (Secretary of Defense may provide assistance in support of Department of Justice activities during

situations involving bombings of places of public use, Government facilities, public transportation systems, and

infrastructure facilities);

10 U.S.C. § 284 (Secretary of Defense may provide support for the counterdrug activities or activities to counter

transnational organized crime of any other department or agency of the Federal Government or of any State, local,

tribal, or foreign law enforcement agency for certain purposes).

18 U.S.C. § 831 (Attorney General may request assistance from the Secretary of Defense for enforcement of the

proscriptions against criminal transactions in nuclear materials if an emergency is deemed to exist); 18 U.S.C. §§ 175a,

229E, and 2332e cross reference to the Attorney General’s authority under 10 U.S.C. § 282 to request assistance from

the Secretary in an emergency involving biological weapons, chemical weapons, and weapons of mass destruction

respectively.

42 U.S.C. § 98 (Secretary of the Navy at the request of the Public Health Service may make vessels or hulks available

to quarantine authority at various U.S. ports).

226 U.S. CONST. art. II, § 3, cl.3 (“[T]he President] shall take care that the laws be faithfully executed.”).

227 5 U.S.C. § 301 (2018) (“The head of an Executive department or military department may prescribe regulations for

the government of his department, the conduct of its employees, the distribution and performance of its business, and

the custody, use, and preservation of its records, papers, and property....”).

228 E.g., 21 U.S.C. § 873(b) (“[w]hen requested by the Attorney General, it shall be the duty of any agency or

instrumentality of the Federal Government to furnish assistance, including technical advice, to him for carrying out his

functions under this subchapter; except that no such agency or instrumentality shall be required to furnish the name of,

or other identifying information about, a patient or research subject whose identity it has undertaken to keep

confidential”).

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The final and more commonly accepted proposition is that the phrase “in cases and under

circumstances expressly authorized by ... Act of Congress” demands that the statutory exception

specifically refer to some form of military assistance.229

The Insurrection Acts

The clearest statutory exceptions to the Posse Comitatus Act are found in the Insurrection Acts,

described above, in which Congress has delegated authority to the President to call forth the

military during an insurrection or civil disturbance. The modern version has changed little from

the original enactments,230 and is now found in Chapter 13 of Title 10, U.S. Code.231 The three

main authorities differ according to which constitutional provision they are meant to implement,

but the provisions have often been used together or without specifying which part of Chapter 13

of Title 10, U.S. Code, provided the authority.232 In any case where the President considers it

necessary to invoke the authority to use the militia or Armed Forces under these provisions, he is

required by 10 U.S.C. Section 254 to issue a proclamation immediately ordering “insurgents to

disperse and retire peaceably to their abodes within a limited time.”

The following sections describe the modern authorities and how they have been invoked since the

passage of the Posse Comitatus Act, including some instances where a separate authority may

have been used for similar purposes.

At the Request of a State

Section 251 of Title 10 (previously section 331 of Title 10) authorizes the President to use the

military to suppress an insurrection at the request of a state legislature, or its governor, in the

event the legislature cannot be convened.233 It is meant to fulfill the federal government’s

responsibility to protect states in the event of “domestic violence”234 (although the term

229

The Department of Defense Instruction (DoDI), for example, lists only the military-aid-specific statutes in its

inventory of statutory exceptions, DoDI No. 3025.21, (Encl.3) 1(b)(5) (2013).

230 The 109th Congress changed the name of the U.S. Code chapter from “Insurrection Act” to “Enforcement of the

Laws to Restore Public Order” and amended Section 333 to expand the circumstances in which it might be invoked,

John Warner National Defense Authorization Act for Fiscal Year 2007, P.L. 109-364 § 1076, 120 Stat. 2083, 2404,

(October 17, 2006)). The revised section 333

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