Al-Bihani v. Obama

United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Filed: August 31, 2010

No. 09-5051

GHALEB NASSAR AL-BIHANI,

APPELLANT

v.

BARACK OBAMA, PRESIDENT OF THE UNITED STATES, ET AL.,

APPELLEES

Appeal from the United States District Court

for the District of Columbia

(No. 1:05-cv-01312)

______

On Petition for Rehearing En Banc

______

BEFORE: Sentelle, Chief Judge, and Ginsburg,

Henderson, Rogers, Tatel, Garland, Brown, Griffith, and

Kavanaugh, Circuit Judges.

ORDER

Appellant=s petition for rehearing en banc and the

response thereto were circulated to the full court, and a vote

was requested. Thereafter, a majority of the judges eligible to

participate did not vote in favor of the petition. Upon

2

consideration of the foregoing and the brief of amici curiae, it

is

ORDERED that the petition be denied.

FOR THE COURT:

Mark J. Langer, Clerk

BY: /s/

Michael C. McGrail

Deputy Clerk

* A statement by Chief Judge Sentelle and Circuit Judges

Ginsburg, Henderson, Rogers, Tatel, Garland, and Griffith,

concurring in the denial of rehearing en banc, is attached.

* A statement by Circuit Judge Brown, concurring in the

denial of rehearing en banc, is attached.

* A statement by Circuit Judge Kavanaugh, concurring in the

denial of rehearing en banc, is attached.

* A statement by Senior Circuit Judge Williams is attached.

SENTELLE, Chief Judge, and GINSBURG, HENDERSON,

ROGERS, TATEL, GARLAND, and GRIFFITH, Circuit Judges,

concurring in the denial of rehearing en banc: We decline to

en banc this case to determine the role of international law-of-

war principles in interpreting the AUMF because, as the

various opinions issued in the case indicate, the panel’s

discussion of that question is not necessary to the disposition

of the merits. See Al-Bihani v. Obama, 590 F.3d 866, 871,

873-74 (D.C. Cir. 2010) (panel opinion); id. at 883-85

(Williams, J., concurring in the judgment); Al-Bihani v.

Obama, No. 09-5051, slip op. at 1 (D.C. Cir. Aug. 31, 2010)

(Kavanaugh, J., concurring in the denial of rehearing en

banc); see also Gov’t’s Resp. to Pet. for Reh’g and Reh’g En

Banc at 1-2 (stating that the dispute over the role of the law of

war does not “change[] the outcome”).

BROWN, Circuit Judge, concurring in the denial of

rehearing en banc: Denial is the fate of most requests for en

banc review, and almost all requests meet that fate quietly

without comment from the court. I would prefer to follow the

usual pattern here. But this, it seems, is no usual case.

Neither the government’s response to the request for

rehearing nor the opinions accompanying the denial can be

described as “usual.” Al-Bihani’s petition requests the court

take the radical step of incorporating all of international law

as judicially enforceable constraints on the President’s war

powers. The government responds ambivalently, adopting the

questionable strategy of conceding Al-Bihani’s point, but

nonetheless urging denial of rehearing. Seven members of

this court now vote to deny the petition, but append a cryptic

statement that exhibits no apparent function other than to

mystify. One judge offers a scholarly exegesis on the

unenforceability of international law norms as limits on the

President’s war-making authority under the AUMF. And last,

another judge contributes a separate opinion that conceives of

a brave new role for judges in wartime: that of supervisors of

the battlefield.

These are unusual developments, indeed, and their

cumulative effect is to muddy the clear holding of Al-Bihani

that international law as a whole does not limit the AUMF’s

grant of war powers. Although we have avoided en banc

review, we have done so through the costly expedient of

making a rather common-place judicial proposition

impenetrably obscure. Clarity in law is a virtue. In the

context of war, that virtue becomes a life-and-death necessity.

But there appears to be a countervailing motivation behind the

court’s resistance to Al-Bihani’s holding: an intuition about

the domestic role of international law, one that moves below

the surface of the briefs and opinions of this en banc petition

process. Hoping to avoid a resolution that leaves all parties in

doubt about international law’s relation to the AUMF, I write

2

separately to pull the veil back on that intuition and provide as

much clarity as possible.

The Al-Bihani opinion held as “mistaken” the “premise

that the war powers granted by” the AUMF and other statutes

“are limited by the international laws of war.” Al-Bihani v.

Obama, 590 F.3d 866, 871 (D.C. Cir. 2010). This holding

disposed of Al-Bihani’s international law–based claims and

instead hinged the resolution of his case on “the text of

relevant statutes and controlling domestic caselaw.” Id. at

871–72.

Although Al-Bihani’s rehearing petition challenges the

panel opinion on numerous points, it is his challenge to this

holding that has caused consternation. Seven judges have

embraced a peculiar concurrence that strives to make clear

that the holding was not necessary to the disposition of the

case, providing four citations to that effect. But the

concurrence leaves unclear the reason why this

uncontroversial point is relevant. We grant rehearing when a

panel opinion creates a conflict with Supreme Court or circuit

precedent, or when a case presents a question we deem

exceptionally important. See FED. R. APP. P. 35(a). Neither of

these criteria is affected when an opinion’s disposition is

supported by two independently sufficient alternative

holdings.

Perhaps the seven-member concurrence is implying that

the holding at issue is dictum—a position for which Judge

Williams argued explicitly in his separate opinion at the panel

stage, see Al-Bihani, 590 F.3d at 885 (Williams, J.,

concurring). Under this view, the holding would therefore be

incapable of either creating a conflict with prior law or

presenting an important question. But this notion would be

incorrect. It is a longstanding principle that alternative

3

holdings each possess precedential effect. See United States

v. Title Ins. & Trust Co., 265 U.S 472, 486 (1924) (“[W]here

there are two grounds, upon either of which an appellate court

may rest its decision, and it adopts both, the ruling on neither

is obiter [dictum], but each is the judgment of the court, and

of equal validity with the other.”); see also Woods v.

Interstate Realty Co., 337 U.S. 535, 537 (1949);

Commonwealth of Mass. v. United States, 333 U.S. 611, 623

(1948). Therefore, if the majority of this court believes the

holding at issue would otherwise satisfy one or both of the en

banc rehearing criteria, a grant of rehearing cannot be avoided

by labeling the holding as unnecessary. Nor will future

litigants be able to avoid the holding’s binding authority by

wielding the same label.

Another possible motivation for the concurrence may be

a desire to accommodate both the government’s eager

concession that international law does in fact limit the AUMF

and the government’s argument that its opinion on the matter

is entitled to “substantial deference.”1 Resp. to Petition for

Rehearing, at 6–8 & n.3. But such a motivation would be

illegitimate. Contrary to the government’s claim, its preferred

statutory interpretation warrants no deference from this court.

A “pure question of statutory construction [is] for the courts

to decide,” INS v. Cardoza-Fonseca, 480 U.S. 421, 446

(1987), and doing so—even when a statute concerns foreign

affairs—is “well within the province of the Judiciary,” Repub.

of Austria v. Altmann, 541 U.S. 677, 701 (2004). Of course,

courts are highly deferential when reviewing challenges to

1

Judge Kavanaugh reads this part of the government’s brief

differently than I do, seeing it as a conflicted argument that leaves

doubt over whether the government truly means what it says. See

infra, at 75–77 (Kavanaugh, J., concurring in denial of en banc

rehearing). I agree the government’s brief is conflicted as a general

matter, but on this point I believe its claim to deference is clear.

4

executive actions taken pursuant to a grant of wide discretion

“to affect a situation in a foreign territory.” United States v.

Curtiss-Wright Export Corp., 299 U.S. 304, 321 (1936). We

will refrain from requiring “narrowly definite standards by

which the President is to be governed” and will not lightly

endeavor to “limit[] or embarrass[] such powers.” Id. at 322.2

However, even when courts consider the Executive’s historic

practice to inform the interpretation of a statute, they are not

imbuing the President with judicial power.

I sense, then, something more significant than a narrow

concern over dictum or deference at work in the seven-

member concurrence. There is in the scholarly community an

intuition that domestic statutes do not stand on their own

authority, but rather rest against the backdrop of international

norms. This intuition has taken many argumentative forms,

some more emphatic than others. For instance, there are those

scholars who believe domestic statutes are merely suggestive

wordings to which courts can and should append international

legal norms, regardless of congressional intent.3 Others are

more shy, imparting to Congress a general intent to legislate

in conformity with international law and therefore reasoning

that all statutes, unless containing a clear statement otherwise,

2

This was, in fact, precisely the sort of deference the government

received in the panel decision.

3

See, e.g., Jeremy Waldron, Foreign Law and the Modern Ius

Gentium, 119 HARV. L. REV. 129, 144 (2005) (proposing courts

resort to norms located in a universal “ius gentium” to treat

“problems that arise in our courts as though they were questions of

legal science”); Jonathan Turley, Dualistic Values in the Age of

International Legisprudence, 44 HASTINGS L.J. 185, 265, 271

(1993) (advocating courts shift “the emphasis away from

determining congressional intent toward upholding international

principles” and “serve a central political function in the developing

transnational arena”).

5

should be read by courts to incorporate international legal

norms.4 However this intuition is phrased, perhaps the

majority of judges on this court are apprehensive about

unambiguously rejecting it. So, even though the panel

decision foreclosed the idea, the short concurrence may

represent a wish to leave open a possibility—however

slight—that domestic statutes are in fact subordinate to an

overarching international legal order.

If that is their wish, it is a curious one. The idea that

international norms hang over domestic law as a corrective

force to be implemented by courts is not only alien to our

caselaw, but an aggrandizement of the judicial role beyond

the Constitution’s conception of the separation of powers.

See United States v. Yunis, 924 F.2d 1086, 1091 (D.C. Cir.

1991) (“[T]he role of judges . . . is to enforce the Constitution,

laws, and treaties of the United States, not to conform the law

of the land to norms of customary international law.”). That

aggrandizement is clear in the more extreme scholarly

opinions calling for courts to ignore congressional intent in

favor of international norms. And it is only slightly better

disguised in the superficially restrained claims that Congress

intends to conform its actions with global ideals, and that a

clear statement is required if courts are to be prevented from

reading international law into statutory text. Traditional clear

statement rules are justified on the basis of preserving statutes

against possible nullification by a constitutional value,

4

See, e.g., Ingrid Brunk Wuerth, Authorizations for the Use of

Force, International Law, and the Charming Betsy Canon, 46 B.C.

L. REV. 293, 334–36, 357 (2005); Ralph G. Steinhardt, The Role of

International Law as a Canon of Domestic Statutory Construction,

43 VAND. L. REV. 1103, 1112, 1115 (1990) (positing a

“presumption that Congress intends to conform its statutes to

international standards” in the “absence of a clear statement of

repudiation by Congress”).

6

keeping both Congress and the judiciary within their

constitutional capacities.5 However, a demand that Congress

clearly enunciate the inapplicability of international norms is

not premised on any constitutional value; nothing in the

Constitution compels the domestic incorporation of

international law. Instead, what such a demand protects is a

policy preference, imputing to Congress a general posture

toward international restrictions and erecting the highest

interpretive hurdle to the legitimate prerogative of Congress

to legislate apart from them. This is a restrained search for

legislative “intent” only in the most Orwellian sense—one

that grants judges license to usurp the legislative role and

dictate to Congress what it is supposed to think. Surprisingly,

proponents of this idea actually claim it guards the separation

of powers. See Wuerth, supra, at 349–50. But if that is the

case, then the cure is truly worse than the disease.

I see much of this scholarly idea in Judge Williams’

separate opinion. While purporting to share Judge

Kavanaugh’s concern about using “gauzy notions of

international law to rein in the executive’s conduct of military

operations,” infra, at 7 (opinion of Williams, J.), Judge

Williams offers a hazy but ominous hermeneutics. Its

animating premise is that Boumediene v. Bush, 128 S. Ct.

2229 (2008), used the Suspension Clause to create an opening

through which the Judiciary now—as a constitutional

matter—“monitor[s]” and “supervise[s] the battlefield

conduct of the U.S. military.” Infra, at 7–8 (opinion of

Williams, J.). In executing this supervisory role, the Judiciary

5

See William N. Eskridge, Jr. & Philip P. Frickey, Quasi-

Constitutional Law: Clear Statement Rules as Constitutional

Lawmaking, 45 VAND. L. REV. 593, 599–609 (1992) (discussing

the constitutional concerns behind canons such as the constitutional

avoidance canon, the rule of lenity, and the presumption in favor of

judicial review).

7

should survey the spectrum of “international discourse,”

picking and choosing those propositions that exhibit—by the

Judiciary’s lights—“serious reasoning,” “consistent[] and

evenhanded[] appli[cation],” and “practical[ity]” to the point

where they are suitable to control the President’s conduct of

war. Id. at 2, 7. Judge Williams states these propositions

matter-of-factly, even blithely, as routine matters of statutory

interpretation. But that nonchalance is only a mask for what

is, at its core, a radical and sweeping claim, one at odds with

our Constitution and caselaw.

The Constitution entrusts the President—not the

Judiciary—with the conduct of war. “The Framers . . . did not

make the judiciary the overseer of our government,”

Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579, 594

(1952) (Frankfurter, J., concurring), so Boumediene cannot be

read—as Judge Williams suggests—to override that basic

notion and hand courts authority to deem international norms

as binding commands on the Commander-in-Chief. Such a

reading would be in tension with the Supreme Court’s

recognition that courts are “hardly . . . competent” in the

realm of foreign affairs, Banco Nacional de Cuba v.

Sabbatino, 376 U.S. 398, 410 (1964), and with the

constitutional principle that prohibits even Congress, let alone

the Judiciary, from “interfer[ing] with the [Executive’s]

command of forces and the conduct of campaigns,” Ex Parte

Milligan, 71 U.S. (4 Wall.) 2, 139 (1866) (Chase, C.J.,

concurring).

Further, Judge Williams’ proposed role for the Judiciary

goes far beyond the role the Supreme Court envisioned in

Hamdi v. Rumsfeld and Boumediene. The Hamdi plurality

forecast a restrained process that “meddles little, if at all, in

the strategy or conduct of war, inquiring only into the

appropriateness of continuing to detain an individual claimed

8

to have taken up arms against the United States.” 542 U.S.

507, 535 (2004). It seems farfetched that “inquiring only into

the appropriateness” of detention should be freighted with the

awesome power of deciding which international constraints to

enforce against the President. In a similar vein, the Court in

Boumediene was circumspect about crafting any substantive

rules to control the President’s war powers, repeating that it

was not addressing the “content of the law that governs

petitioners’ detention,” leaving it to the political branches first

to engage in a “debate about how best to preserve

Constitutional values while protecting the Nation from

terrorism.” 128 S. Ct. at 2277. Boumediene’s holding

concerned the jurisdiction of U.S. courts over Guantanamo

habeas petitions, and it strains the jurisdictional nature of that

holding to draw from it a substantive judicial power to spin

international discourse into binding domestic law. It is no

wonder then that Judge Williams does not offer any language

from Boumediene to support his theory of an expanded

judicial role in military affairs.

This sprint into judicial immodesty cannot be redeemed

by Judge Williams’ argument that international law parallels

traditional tools of statutory interpretation, and that by turning

to it for substantive meaning courts are only divining the

intent of Congress. I am unaware of any federal judicial

opinion—and Judge Williams cites none—that has ever

before characterized international discourse as a traditional

tool of statutory interpretation on par with legislative history,

usage in other domestic statutes and cases, or dictionary

definitions. The varied process by which international law is

made—through treaty, tribunal decision, and the constant

churn of state practice and opinio juris—shares few, if any, of

the qualities that give the traditional sources of interpretation

their authority. Courts turn to legislative history because it

comes from the mouths of legislators and therefore arguably

9

sheds light on their intentions and understandings. Courts

examine the usage of terms in other statutes and judicial

decisions because our law is a closed and coherent system that

strives for internal consistency. And courts consult

dictionaries for the same reason most people do: our law, like

the rest of our society, is dependent on language’s technical

meaning among American English speakers. On none of

these grounds can the use of international law be justified.

As Judge Kavanaugh explains in his detailed

concurrence, international norms outside of those explicitly

incorporated into our domestic law by the political branches

are not part of the fabric of the law enforceable by federal

courts after Erie. See infra, at 15–21 (Kavanaugh, J.,

concurring in denial of en banc rehearing). They therefore do

not help courts to determine congressional intent or to

recognize the wider coherence of the law. And international

discourse, unlike a dictionary, is anything but a source of

specific, technical, and shared linguistic meaning. Judge

Williams concedes this point, characterizing international law

as often “vague and deficient,” consisting of “gauzy notions”

that are prone to “misuse” by nations for “political

purpose[s],” and subject to official criticism by our elected

representatives. Infra, at 7 (opinion of Williams, J.). How

can sifting through such an unstable and unreliable trove of

meaning be likened to opening a dictionary? How is it

advisable or legitimate for courts to take on such a

treacherous task, especially when the political branches

possess the competency and traditional duty to do the sifting

themselves by domestically incorporating international law

through statute or rendering treaties self-executing?

But suppose we ignore the questionable propriety of

Judge Williams’ interpretive method and endeavor to apply it

in this case. Ironically—and perhaps paradoxically—we

10

likely would double-back to the same conclusion that

international law does not limit the AUMF. The phrase in the

AUMF on which Al-Bihani hinges his argument is “necessary

and appropriate,” which he contends modifies the word

“force” by prohibiting conduct not approved by international

law. The closest analogy in domestic law is the phrase

“necessary and proper,” which, as Judge Kavanaugh notes in

his concurrence, has in its constitutional and statutory

provenance been consistently interpreted to broaden rather

than to constrain discretion. See, e.g., Legal Tender Cases, 79

U.S. (12 Wall.) 457, 550 (1870) (“[T]he auxiliary powers,

those necessary and appropriate to the execution of other

powers singly described . . . are grouped in the last clause of

section eight of the first article [the Necessary and Proper

Clause].”) (emphasis added). Turning to international

materials does not yield a different meaning. Usage of the

phrase “necessary and appropriate” on the international plane

grants nations wide discretion to act and does not purport to

constrain them with international law. One example—among

many—is U.N. Security Council Resolution 1624, which in

three separate clauses calls upon states “to take all measures

as may be necessary and appropriate and in accordance with

their obligations under international law” to counter

incitement to terrorist acts. S.C. Res. 1624, ¶¶ 1, 3, U.N. Doc.

S/RES/1624 (Sept. 14, 2005) (emphasis added); see also id.

pmbl. That the Security Council felt the need to append

international law obligations to “necessary and appropriate”—

three times, no less—indicates the phrase does not

automatically incorporate such obligations.

But putting aside the preceding discussion (and the odd

conceptual loop it creates), I reiterate that consulting

international sources in that manner is not something judges

have in their interpretive toolbox. The only generally

applicable role for international law in statutory interpretation

11

is the modest one afforded by the Charming Betsy canon,

which counsels courts, where fairly possible, to construe

ambiguous statutes so as not to conflict with international law.

See RESTATEMENT (THIRD) OF THE FOREIGN RELATIONS LAW

OF THE UNITED STATES § 114 (1987); see also Sampson v.

Fed. Repub. of Germany, 250 F.3d 1145, 1152 (7th Cir.

2001).6 However, Judge Williams does not appear to confine

international law to such a narrow space. By including

international discourse among the traditional tools available to

courts when interpreting statutes, Judge Williams is not

limiting the application of international law to ambiguous

statutory text. Generally, a statute’s text is only ambiguous

if, after “employing traditional tools of statutory

construction,” a court determines that Congress did not have a

precise intention on the question at issue. Chevron, U.S.A.,

Inc. v. Natural Res. Def. Council, Inc., 467 U.S. 837, 843 n.9

(1984). It is at this point—analogous to Chevron Step Two—

that the Charming Betsy canon has had any application in

federal courts. But Judge Williams implies that international

law should be consulted in the first instance to influence

6

I note the Charming Betsy canon was not invoked in the panel

opinion because it is not applicable to this case. First, the relevant

text of the AUMF is not ambiguous. The phrase “necessary and

appropriate” is broad, but wide breadth is not tantamount to

ambiguity, particularly when a phrase has a stable interpretive

pedigree. Second, even if the phrase were ambiguous, the canon

only applies to statutory interpretations that would violate

international law. An interpretation declining to place international

legal constraints on the President does not, by itself, place the

United States in violation of international law. It merely affirms the

President’s normal prerogative to observe or abrogate international

obligations. Judge Kavanaugh also details other persuasive reasons

why Charming Betsy does not apply in this case. See infra, at

45–66 (Kavanaugh, J., concurring in the denial of en banc

rehearing).

12

interpretation at the same level as traditional interpretive

tools, making its use predicate to a finding of ambiguity. This

implication has the secondary effect of eviscerating the

limiting principle of the Charming Betsy canon that it only

exerts a negative force on the meaning of statutes, pushing

them away from meanings that would conflict with

international law. Courts do not apply Charming Betsy as an

affirmative indicator of statutory meaning. See, e.g.,

Sampson, 250 F.3d at 1152–53 (holding the Charming Betsy

canon does not require “federal statutes [to be] read to reflect

norms of international law”); Princz v. Fed. Repub. of

Germany, 26 F.3d 1166, 1174 & n.1 (D.C. Cir. 1994)

(rejecting dissent’s argument that statutes must be read

“consistently with international law” and must be presumed to

“incorporate[] standards recognized under international law,”

Princz, 26 F.3d at 1183 (Wald, J., dissenting)). However,

under Judge Williams’ method, I see no reason why courts

would be bound by this rule, since traditional interpretive

sources are normally viewed as indicative of affirmative

meaning. These inconsistencies with the Charming Betsy

canon make clear that Judge Williams’ proposal cannot

possibly be correct. If it were, it would be a mystery why

American jurisprudence would even bother to enunciate an

interpretive canon like the Charming Betsy. Judge Williams’

approach would make that canon vestigial, foolish even—akin

to a canon limiting the use of dictionaries.

Most troubling of all is the grotesque non sequitur that

Congress must have intended to incorporate international law

through the AUMF because it would be odd to think Congress

“embrace[d]” a long history of wartime atrocity, from the

Rape of Nanking to the massacre at Lidice. Judge Williams

may believe that the only barrier that would hold back our

nation from a descent into Nazism is an enlightened judiciary

standing at the precipice, wielding international norms our

13

polity is presumably unable to muster from within.7 But that

belief cannot change the plain text of the AUMF, its

legislative history, or the longstanding congressional practice

of granting “the President a degree of discretion and freedom

from statutory restriction” necessary to carry out his foreign

affairs duties, Curtiss-Wright, 299 U.S. at 320.

There is no indication that the AUMF placed any

international legal limits on the President’s discretion to

prosecute the war and, in light of the challenge our nation

faced after September 11, 2001, that makes eminent sense.

Confronted with a shadowy, non-traditional foe that

succeeded in bringing a war to our doorstep by asymmetric

means, it was (and still is) unclear how international law

applies in all respects to this new context. The prospect is

very real that some tradeoffs traditionally struck by the laws

of war no longer make sense. That Congress wished the

President to retain the discretion to recalibrate the military’s

strategy and tactics in light of circumstances not contemplated

by our international obligations is therefore sensible, and

reflects the traditional sovereign prerogative to violate

international law or terminate international agreements. See

Garcia-Mir v. Meese, 788 F.2d 1446, 1455 (11th Cir. 1986)

(“[T]he power of the President to disregard international law

in service of domestic needs is reaffirmed.”); RESTATEMENT

(THIRD) OF THE FOREIGN RELATIONS LAW OF THE UNITED

STATES § 339 (describing power of the President to suspend or

terminate international agreements).8

7

Our nation has in fact established workable norms forbidding such

crimes against humanity, as detailed by Judge Kavanaugh. See

infra, at 6–7, 39–45 (Kavanaugh, J., concurring in denial of en banc

rehearing).

8

That courts cannot enforce non–self-executing or non-

incorporated international law against the President does not imply

the United States would escape consequences of breach on the

14

The only way a court could reach the opposite conclusion

is to go beyond the AUMF’s text, freeing it—as Judge

Williams suggests—to appeal to an international meta-

narrative, one activated whenever a legal issue touches on

matters that strike the judge as transnational in flavor. Judges

act prudently when they consciously forego opportunities for

policymaking. Therefore, ignoring the text and plain meaning

of a statute to privilege a more creative interpretation is the

antithesis of prudence. And, in a time of war, it has the

inconvenient effect of upending more than a century of our

jurisprudence based on an understanding as old as the

Republic: that the “conduct of foreign relations of our

government is committed by the Constitution to the executive

and legislative . . . departments,” not to the judiciary. Oetjen

v. Cent. Leather Co., 246 U.S. 297, 302 (1918).

The only proper judicial role in this case is the truly

modest route taken by the panel opinion in Al-Bihani. We

read “necessary and appropriate” in its traditional sense,

taking Congress at its word that the President is to have wide

discretion. This is a modest course because the President

retains the leeway to implement his authority as broadly or

narrowly as he believes appropriate—consistent with

international law or not—and the legislature, in turn, may add

whatever limits or constraints it deems wise as the war

progresses. This ensures that wartime decisions will be

informed by the expertise of the political branches, stated in a

clear fashion, and that the decisionmakers will be accountable

to the electorate.

international plane. Whether to incur such consequences is part of

the political calculus the President performs when deciding to

disregard international obligations.

15

None of those benefits accrue if the conduct of the

military is subject to judicial correction based on norms of

international discourse. Such an approach would place

ultimate control of the war in the one branch insulated from

both the battlefield and the ballot box. That would add further

illegitimacy to the unpredictable and ad hoc rules judges

would draw from the primordial stew of treaties, state

practice, tribunal decisions, scholarly opinion, and foreign law

that swirls beyond our borders. It is no comfort to the

military to say, as Judge Williams does, that courts will only

apply international rules they deem to possess the qualities of

serious reason, evenhandedness, and practicality. Those are

not judicially manageable standards. Those are buzzwords,

the pleasing sound of which nearly lulls the mind into missing

the vision of judicial supremacy at the heart of Judge

Williams’ opinion.

KAVANAUGH, Circuit Judge, concurring in the denial of

rehearing en banc:

In the 2001 Authorization for Use of Military Force,

Congress authorized the President to wage war against al

Qaeda and the Taliban. That war continues. At the

President’s direction, the U.S. military is detaining Al-Bihani

as an enemy belligerent in the ongoing conflict. Al-Bihani

has asked this Court to order his release from U.S. military

custody. He argues that international-law principles prohibit

his continued detention.

The premise of Al-Bihani’s plea for release is that

international-law norms are judicially enforceable limits on

the President’s war-making authority under the AUMF. Even

accepting that premise, Al-Bihani cannot prevail in this case.

As the panel opinion correctly concludes, Al-Bihani’s

arguments misconstrue international law and overlook

controlling federal statutes such as the Military Commissions

Acts of 2006 and 2009.

In any event, as the panel opinion also states, the premise

of Al-Bihani’s argument is incorrect. International-law norms

that have not been incorporated into domestic U.S. law by the

political branches are not judicially enforceable limits on the

President’s authority under the AUMF. This separate opinion

explains at great length my reasons for reaching that

conclusion.

Al-Bihani’s invocation of international law raises two

fundamental questions. First, are international-law norms

automatically part of domestic U.S. law? Second, even if

international-law norms are not automatically part of

domestic U.S. law, does the 2001 AUMF incorporate

international-law principles as judicially enforceable limits on

the President’s wartime authority under the AUMF? The

answer to both questions is no.

2

First, international-law norms are not domestic U.S. law

in the absence of action by the political branches to codify

those norms. Congress and the President can and often do

incorporate international-law principles into domestic U.S.

law by way of a statute (or executive regulations issued

pursuant to statutory authority) or a self-executing treaty.

When that happens, the relevant international-law principles

become part of the domestic U.S. law that federal courts must

enforce, assuming there is a cognizable cause of action and

the prerequisites for federal jurisdiction are satisfied. But in

light of the Supreme Court’s 1938 decision in Erie Railroad

Co. v. Tompkins, 304 U.S. 64 (1938), which established that

there is no federal general common law, international-law

norms are not enforceable in federal courts unless the political

branches have incorporated the norms into domestic U.S. law.

None of the international-law norms cited by Al-Bihani has

been so incorporated into domestic U.S. law.

Second, the 2001 AUMF does not expressly or impliedly

incorporate judicially enforceable international-law limits on

the President’s direction of the war against al Qaeda and the

Taliban. In authorizing the President to employ force, the

AUMF authorizes the President to command the U.S. military

to kill, capture, and detain the enemy, as Commanders in

Chief traditionally have done in waging wars throughout

American history. Congress enacted the AUMF with

knowledge that the U.S. Constitution and other federal

statutes would limit the President’s conduct of the war. But

neither the AUMF’s text nor contemporaneous statements by

Members of Congress suggest that Congress intended to

impose judicially enforceable international-law limits on the

President’s authority under the AUMF.

3

Moreover, for three alternative reasons, the Charming

Betsy canon does not authorize courts to employ international-

law norms when interpreting a statute like the AUMF that

broadly authorizes the President to wage war against a foreign

enemy. To begin with, in the post-Erie era, the canon does

not permit courts to alter their interpretation of federal statutes

based on international-law norms that have not been

incorporated into domestic U.S. law. Indeed, since Erie was

decided, the Supreme Court has applied that canon only to

support the presumption that a federal statute does not apply

extraterritorially. Even if one disagrees with that initial

reason for not applying Charming Betsy, however, courts may

not invoke the canon against the Executive. Under basic

principles of administrative law, the Executive generally has

the authority to interpret ambiguous statutes within the

bounds of reasonableness and, in so doing, to weigh

international-law considerations as much or as little as the

Executive sees fit. And even if one also disagrees with that,

there is another, still narrower reason why Charming Betsy

does not apply here: Courts have never applied the Charming

Betsy canon against the Executive to limit the scope of a

congressional authorization of war. For good reason: To the

extent there is ambiguity in a statutory grant to the President

of war-making authority, the President – not an international

tribunal or international law – is to resolve the ambiguity in

the first instance. See Dep’t of the Navy v. Egan, 484 U.S.

518, 530 (1988); cf. Chevron U.S.A. Inc. v. Natural Res. Def.

Council, Inc., 467 U.S. 837, 842-45 (1984).

Al-Bihani relatedly suggests that Hamdi v. Rumsfeld, 542

U.S. 507 (2004), already held that the AUMF incorporates

international-law norms and that courts therefore must

enforce international-law limits against the President. That is

incorrect: Hamdi never stated that the AUMF incorporates

judicially enforceable international-law limits on the

4

President’s authority, which of course would have been a

momentous and unprecedented holding.

In sum, a federal court lacks legitimate authority to

interfere with the American war effort by ordering the

President to comply with international-law principles that are

not incorporated into statutes, regulations, or self-executing

treaties.

Before proceeding to the analysis of these issues, I

emphasize three overarching points about the position

advanced in this separate opinion.

First, this opinion recognizes and reinforces the

traditional roles of Congress, the President, and the Judiciary

in national-security-related matters – roles enduringly

articulated in Justice Jackson’s separate opinion in

Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579

(1952). Courts enforce constitutionally permissible

constraints imposed by Congress on the President’s war

powers. See Hamdan v. Rumsfeld, 548 U.S. 557 (2006);

Youngstown, 343 U.S. at 634-655 (Jackson, J., concurring);

see generally David J. Barron & Martin S. Lederman, The

Commander in Chief at the Lowest Ebb – Framing the

Problem, Doctrine, and Original Understanding, 121 HARV.

L. REV. 689, 761-66 (2008). So, too, courts enforce judicially

manageable limits imposed by the U.S. Constitution on the

President’s war powers. See Boumediene v. Bush, 128 S. Ct.

2229 (2008); Hamdi, 542 U.S. 507. But courts may not

interfere with the President’s exercise of war powers based on

international-law norms that the political branches have not

seen fit to enact into domestic U.S. law.

Second, the limited authority of the Judiciary to rely on

international law to restrict the American war effort does not

5

imply that the political branches should ignore or disregard

international-law norms. The principles of the international

laws of war (and of international law more generally) deserve

the respect of the United States. Violating international-law

norms and breaching international obligations may trigger

serious consequences, such as subjecting the United States to

sanctions, undermining U.S. standing in the world

community, or encouraging retaliation against U.S. personnel

abroad. Therefore, Congress and the President are often well-

advised to take account of international-law principles when

considering potential legislation or treaties. And even when

international-law norms have not been incorporated into

domestic U.S. law, the Executive Branch, to the extent

permissible under its constitutional and statutory authority, is

often wise to pay close attention to those norms as a matter of

sound policy, international obligation, or effective foreign

relations. See, e.g., Harold Hongju Koh, Legal Adviser, U.S.

Department of State, The Obama Administration and

International Law: Address at the Annual Meeting of the

American Society of International Law (Mar. 25, 2010); John

B. Bellinger III, Legal Adviser, U.S. Department of State,

Testimony Before the Senate Committee on Foreign Relations

(April 15, 2008), reprinted in part in DIGEST OF UNITED

STATES PRACTICE IN INTERNATIONAL LAW 2008, at 887-88

(Elizabeth R. Wilcox ed.); Letter from Gen. Colin L. Powell

to Sen. John McCain (Sept. 13, 2006), reprinted at 152 CONG.

REC. S10,412 (daily ed. Sept. 28, 2006).

But in our constitutional system of separated powers, it is

for Congress and the President – not the courts – to determine

in the first instance whether and how the United States will

meet its international obligations. When Congress and the

President have chosen not to incorporate international-law

norms into domestic U.S. law, bedrock principles of judicial

6

restraint and separation of powers counsel that courts respect

that decision.

Third, consistent with that constitutional division of

authority, Congress has enacted a significant body of

legislation to prohibit certain wartime actions by the

Executive and military that contravene American values. For

example, Congress has adopted a detailed and extensive

Uniform Code of Military Justice, which governs many

aspects of military conduct. See 10 U.S.C. §§ 801-946.

Congress also has passed separate laws banning genocide and

war crimes, including laws criminalizing grave breaches of

the Geneva Conventions (such as rape, torture, and murder).

See, e.g., 18 U.S.C. §§ 1091, 2441. In addition, acting

pursuant to congressional authorization, the Executive Branch

has promulgated numerous legally binding rules that regulate

wartime conduct of the military. See, e.g., Enemy Prisoners

of War, Retained Personnel, Civilian Internees and Other

Detainees, Army Reg. 190-8, § 1-1(b) (Oct. 1, 1997). Those

laws, along with many other statutes and regulations, together

constitute a comprehensive body of domestic U.S. laws of

war.

In his thoughtful opinion in connection with the denial of

rehearing, Judge Williams says that it “would be an odd

member of Congress who supposed that in authorizing the use

of military force he was embracing uses equivalent to all such

uses that have ever occurred: think Nanking 1937-38; Katyn

1940; Lidice 1942; My Lai 1968.” Williams Op. at 2-3. I

agree entirely with Judge Williams on that point, but not

because I believe Congress intended for U.S. courts to enforce

international-law norms against the Executive. Rather, when

Congress authorized war in 2001, it did so knowing that

domestic U.S. law already prohibited a variety of improper

wartime conduct. Judge Williams’ worrisome hypotheticals

7

are thus already taken care of – by the domestic U.S. laws of

war – and do not support his suggestion that the AUMF

incorporates international-law norms. Notably, Judge

Williams points to no examples of violations of international

law that would be contrary to fundamental American values

but that are not already independently prohibited by domestic

U.S. law. There is a good deal of overlap between the

international laws of war and domestic U.S. laws regulating

war. When there is divergence, however, Congress and the

President – not the courts – have the authority in the first

instance to decide whether and how to conform U.S. law to

international law.1

I

Four categories of law are relevant to this case: federal

statutes; self-executing treaties made by the President with the

concurrence of two-thirds of the Senate; non-self-executing

treaties made by the President with the concurrence of two-

thirds of the Senate; and customary international law.2

1

As the opinions concurring in the denial of rehearing en banc

reveal, this question about the relevance of international law to the

AUMF is difficult and intricate. And it is only one of many

complicated issues that the courts have had to grapple with in

conducting habeas proceedings for Guantanamo detainees. In that

regard, it is appropriate here to acknowledge the extraordinary

efforts of the District Judges of this Circuit in expeditiously

addressing and resolving these important and often novel questions.

Even when this Court might disagree with a District Court decision,

that disagreement is with respect and appreciation for the dedicated

work of the District Court on these matters.

2

A self-executing treaty is one that “has automatic domestic

effect as federal law upon ratification.” Medellín v. Texas, 552 U.S.

491, 505 n.2 (2008).

8

Those four categories do not share the same status in U.S.

law. As I will explain, statutes and self-executing treaties are

domestic U.S. law and thus enforceable in U.S. courts. By

contrast, non-self-executing treaties and customary

international law are not domestic U.S. law. See Medellín v.

Texas, 552 U.S. 491 (2008); Sosa v. Alvarez-Machain, 542

U.S. 692 (2004). Only when international-law principles are

incorporated into a statute or a self-executing treaty do they

become domestic U.S. law enforceable in U.S. courts.

In this case, none of the purported international-law

principles cited by Al-Bihani has been incorporated into a

statute or self-executing treaty. Those principles are therefore

not part of the domestic law of the United States and, on their

own, do not authorize a U.S. court to order Al-Bihani’s

release from U.S. military detention.

A non-self-executing treaty is one that “does not by itself give

rise to domestically enforceable federal law.” The domestic effect

of such a treaty therefore “depends upon implementing legislation

passed by Congress.” Id.

Customary international law is a kind of international common

law; it is a body of rules and principles said to arise informally from

the general and consistent practice of nations. See RESTATEMENT

(THIRD) OF FOREIGN RELATIONS LAW OF THE UNITED STATES

§ 102(2) (1987). Evidence of customary international law includes

judgments and opinions of international tribunals, such as the

International Court of Justice (whose judges are approved by the

U.N. General Assembly and Security Council); judgments and

opinions of other nations’ judicial tribunals; and scholarly writings.

Id. § 103.

9

A

In our constitutional system, international-law norms may

achieve the status of domestic U.S. law through two

mechanisms: incorporation into a statute (or legally binding

executive regulation adopted pursuant to a statute) or

incorporation into a self-executing treaty.

First, international-law norms may be incorporated into

legislation approved by a majority in both Houses of

Congress and signed by the President (or enacted over a

presidential veto, or by operation of the Constitution’s ten-day

rule). See U.S. CONST. art. I, § 7.

The important role Congress plays in this sphere is

apparent from the text of the Constitution, which specifically

authorizes Congress to “define and punish . . . Offences

against the Law of Nations.” Id. art. I, § 8, cl. 10. The

delegates to the Constitutional Convention expressly assigned

that power to Congress because, as Gouverneur Morris aptly

noted at the Convention, international-law principles are

“often too vague and deficient to be a rule” without

implementing legislation. 2 THE RECORDS OF THE FEDERAL

CONVENTION OF 1787, at 615 (Max Farrand ed., rev. ed.

1937); see also United States v. Smith, 18 U.S. 153, 159

(1820) (international law “cannot, with any accuracy, be said

to be completely ascertained and defined in any public code

recognised by the common consent of nations”).

Consistent with that constitutionally assigned role,

Congress sometimes enacts statutes to codify international-

law norms derived from non-self-executing treaties or

customary international law, or to fulfill international-law

obligations. The Foreign Sovereign Immunities Act of 1976

is a good example of that kind of legislation. The Act

10

governs federal courts’ jurisdiction to entertain suits against

foreign nations. See 28 U.S.C. §§ 1602-1611. As the

Supreme Court has recognized, “one of the primary purposes

of the FSIA was to codify . . . extant international law.”

Samantar v. Yousuf, 130 S. Ct. 2278, 2289 (2010). Likewise,

the War Crimes Act criminalizes certain conduct – including

torture, rape, and hostage-taking – committed in war by or

against U.S. nationals or members of the U.S. Armed Forces.

The Act provides that this conduct “constitutes a grave breach

of common Article 3” of the 1949 Geneva Conventions. See

18 U.S.C. § 2441(c)(3), (d)(1). Similarly, the Genocide

Convention Implementation Act of 1987 criminalizes

participation in genocide and thereby implements a non-self-

executing treaty to which the United States is a party. See id.

§§ 1091-1093; Convention on the Prevention and Punishment

of the Crime of Genocide, adopted Dec. 9, 1948, S. TREATY

DOC. NO. 81-15; see also Demjanjuk v. Meese, 784 F.2d

1114, 1116 (D.C. Cir. 1986) (Bork, J., in chambers)

(Genocide Convention is not self-executing).

Congress also has passed several laws designed to

implement certain aspects of the international Convention

Against Torture, a non-self-executing treaty to which the

United States is a party. See Convention Against Torture and

Other Cruel, Inhuman or Degrading Treatment or

Punishment, adopted Dec. 10, 1984, S. TREATY DOC. NO.

100-20; Wang v. Ashcroft, 320 F.3d 130, 140 (2d Cir. 2003).

For example, the Torture Victim Protection Act of 1991

creates a civil cause of action to recover damages for torture

committed by foreign officials, “in part to fulfill the

Convention’s mandate that ratifying nations take action to

ensure that torturers are held legally accountable for their

actions.” Price v. Socialist People’s Libyan Arab Jamahiriya,

294 F.3d 82, 92 (D.C. Cir. 2002); see 18 U.S.C. § 1350 note.

Likewise, the federal criminal torture statute establishes

11

criminal penalties for U.S. nationals (and non-U.S. persons

present in the United States) who commit or conspire to

commit torture outside U.S. territory; that statute fulfills U.S.

obligations under Articles 4 and 5 of the Convention. 18

U.S.C. §§ 2340-2340A; see Renkel v. United States, 456 F.3d

640, 644 (6th Cir. 2006).3

When incorporating international-law norms into

domestic U.S. law, Congress sometimes simply enacts

statutes that refer generically to “international law” (or some

variation thereof) without further defining what international

law requires. For example, federal piracy statutes permit the

capture and forfeiture of vessels used for, and the

imprisonment of individuals who commit, acts of “piracy as

defined by the law of nations.” 18 U.S.C. § 1651; 33 U.S.C.

§§ 384-385; see Ex parte Quirin, 317 U.S. 1, 29 (1942).

Similarly, Congress has authorized the President to use

military force to detain foreign vessels at American ports

when such action is permitted “by the law of nations or the

treaties of the United States.” 22 U.S.C. § 462. It has also

empowered the President to impose sanctions on foreign

3

Relatedly, international-law norms also may be incorporated

into domestic U.S. law by way of executive regulations that have

been adopted pursuant to statutory authorization. For example,

Army Regulation 190-8 governs the treatment of enemy prisoners

of war and other detainees in the custody of the U.S. Armed Forces.

The introduction to that regulation states that it “implements

international law, both customary and codified, relating to” military

detention, including the 1949 Geneva Conventions. Enemy

Prisoners of War, Retained Personnel, Civilian Internees and Other

Detainees, Army Reg. 190-8, § 1-1(b) (Oct. 1, 1997); see 10 U.S.C.

§§ 121, 3061, 6011, 8061 (authorizing issuance of military

regulations). Throughout this opinion, when I refer to domestic

U.S. law, the reference includes statutorily authorized executive

regulations that have the force of law.

12

countries that use chemical or biological weapons “in

violation of international law.” Id. §§ 5604-5605. In

addition, Article 21 of the Uniform Code of Military Justice

allows military commissions to the extent permitted by statute

or the “law of war.” 10 U.S.C. § 821; see Hamdan v.

Rumsfeld, 548 U.S. 557, 593 (2006) (Congress “preserved

what power, under the Constitution and the common law of

war, the President had had before 1916 to convene military

commissions – with the express condition that the President

and those under his command comply with the law of war”).

Congress likewise has repeatedly directed Executive agencies

to comply with “general” or “generally recognized”

“principles of international law” when administering statutes

that involve activities in international waters. See, e.g., 10

U.S.C. § 113 note (Sunken Military Craft, § 1406(b))

(protection of sunken military vessels); 16 U.S.C. § 1435(a)

(management of national marine sanctuaries); 30 U.S.C.

§ 1421 (issuance of permits for deepwater mining operations);

42 U.S.C. § 9119 (issuance of permits for ocean thermal

energy conversion facilities).

Second, in addition to being incorporated into a statute

(or executive regulation adopted pursuant thereto),

international-law principles may become part of domestic

U.S. law by means of a self-executing treaty that is made by

the President with the concurrence of two-thirds of the Senate.

See U.S. CONST. art. II, § 2, cl. 2; Medellín, 552 U.S. at 505

n.2; Foster v. Neilson, 27 U.S. 253, 314 (1829). A self-

executing treaty is one that “reflect[s] a determination by the

President who negotiated it and the Senate that confirmed it

that the treaty has domestic effect.” Medellín, 552 U.S. at

521. By contrast, a treaty is non-self-executing when it “reads

like a compact between independent nations that depends for

the enforcement of its provisions on the interest and the honor

of the governments which are parties to it.” Id. at 508-09

13

(quoting Head Money Cases, 112 U.S. 580, 598 (1884))

(internal quotation marks omitted).

Numerous bilateral treaties – agreements between the

United States and one other nation – are self-executing. For

example, the United States has entered into many bilateral

Friendship, Commerce, and Navigation treaties, which define

the civil, property, and commercial rights each treaty country

will afford to nationals of the other. Courts have routinely

held such treaties to be self-executing. See Medellín, 552

U.S. at 521 (“we have held that a number of the ‘Friendship,

Commerce, and Navigation’ Treaties . . . are self-executing”);

Kolovrat v. Oregon, 366 U.S. 187, 191, 196 (1961) (Treaty of

Commerce between United States and Serbia enforceable in

U.S. court); Clark v. Allen, 331 U.S. 503, 508, 517 (1947)

(Treaty of Friendship, Commerce, and Consular Rights

between United States and Germany enforceable in U.S.

court); Asakura v. City of Seattle, 265 U.S. 332, 341 (1924)

(Treaty of Commerce and Navigation between United States

and Japan “operates of itself without the aid of any

legislation” and “will be applied and given authoritative effect

by the courts”); McKesson Corp. v. Islamic Republic of Iran,

539 F.3d 485, 488 (D.C. Cir. 2008) (Treaty of Amity,

Economic Relations, and Consular Rights between United

States and Iran, “like other treaties of its kind, is self-

executing”).

Similarly, bilateral extradition treaties are ordinarily

considered self-executing. See, e.g., Cheung v. United States,

213 F.3d 82, 95 (2d Cir. 2000).

Courts have been somewhat more reluctant to find

multilateral treaties self-executing. See, e.g., Andrea Bianchi,

International Law and U.S. Courts: The Myth of Lohengrin

Revisited, 15 EUR. J. INT’L L. 751, 758 (2004); Curtis A.

14

Bradley, International Delegations, the Structural

Constitution, and Non-Self-Execution, 55 STAN. L. REV. 1557,

1588 & n.147 (2003). As one court explained, when a

multilateral treaty is ratified by many nations, “some of which

do not recognize treaties as self-executing,” it is difficult for

courts to “ascribe to the language of the treaty any common

intent that the treaty should of its own force operate as the

domestic law of the ratifying nations.” United States v.

Postal, 589 F.2d 862, 878 (5th Cir. 1979).

However, a multilateral treaty still may be self-executing

if its terms indicate that the President and Senate so intended.

An example is the Warsaw Convention, a treaty entered into

by President Franklin Roosevelt with the concurrence of the

U.S. Senate in 1934. It governs the liability of air carriers for

passenger injuries and lost cargo. See Convention for the

Unification of Certain Rules Relating to International

Transportation by Air, opened for signature Oct. 12, 1929, 49

Stat. 3000. The Supreme Court has held that “no domestic

legislation is required to give the [Warsaw] Convention the

force of law in the United States.” Trans World Airlines, Inc.

v. Franklin Mint Corp., 466 U.S. 243, 252 (1984); see, e.g., El

Al Israel Airlines, Ltd. v. Tsui Yuan Tseng, 525 U.S. 155, 176

(1999); Curtin v. United Airlines, Inc., 275 F.3d 88, 90 (D.C.

Cir. 2001). Some other multilateral treaties also have been

regarded as self-executing, such as the Hague Convention on

the Taking of Evidence Abroad in Civil or Commercial

Matters, the General Inter-American Convention for Trade

Mark and Commercial Protection, and the Vienna Convention

on Consular Relations. See Société Nationale Industrielle

Aérospatiale v. U.S. Dist. Ct. for the S. Dist. of Iowa, 482 U.S.

522, 533 (1987); Bacardi Corp. of America v. Domenech, 311

15

U.S. 150, 161 (1940); Gandara v. Bennett, 528 F.3d 823, 828

(11th Cir. 2008).4

B

By contrast, international-law principles found in non-

self-executing treaties and customary international law, but

not incorporated into statutes or self-executing treaties, are

not part of domestic U.S. law.

The Supreme Court has squarely held that non-self-

executing treaties “are not domestic law.” Medellín, 552 U.S.

at 505 (quotation omitted). Therefore, “responsibility for

transforming an international obligation arising from a non-

self-executing treaty into domestic law falls to Congress.” Id.

at 525-26.

The Supreme Court has likewise indicated that customary

international law is not automatically part of domestic U.S.

law. See Sosa, 542 U.S. 692. Customary international law is

said to arise from the “general and consistent practice of states

followed by them from a sense of legal obligation.”

RESTATEMENT (THIRD) OF FOREIGN RELATIONS LAW OF THE

UNITED STATES § 102(2) (1987). It is a kind of international

common law. It does not result from any of the mechanisms

specified in the U.S. Constitution for the creation of U.S. law.

For that reason, although norms of customary international

4

To say that a treaty is self-executing does not answer the

analytically distinct question whether the treaty confers individually

enforceable rights or a private cause of action. See Medellín, 552

U.S. at 506 n.3. Thus, a treaty may be self-executing in the sense

that it imposes domestic-law obligations on government officials,

yet the treaty itself may not provide a civil cause of action or other

private remedy for violations of those obligations. Id.; see, e.g.,

McKesson, 539 F.3d at 488-89; Gandara, 528 F.3d at 827-29.

16

law may obligate the United States internationally, they are

not part of domestic U.S. law. Customary-international-law

norms become part of domestic U.S. law only if the norms are

incorporated into a statute or self-executing treaty.

To be sure, there was a time when U.S. courts stated that

customary international law was “part of our law” so that

“where there is no treaty, and no controlling executive or

legislative act or judicial decision, resort must be had to the

customs and usages of civilized nations; and, as evidence of

these, to the works of jurists and commentators.” The

Paquete Habana, 175 U.S. 677, 700 (1900). But that oft-

quoted statement reflected the notion, common in the early

years of the Nation but now discredited, that international law

was part of the general common law that federal courts could

apply. See Sosa, 542 U.S. at 714-15; Erie R.R. Co. v.

Tompkins, 304 U.S. 64, 79 (1938) (historically, the common

law was viewed as “a transcendental body of law outside of

any particular State but obligatory within it unless and until

changed by statute”) (quotation omitted); Curtis A. Bradley &

Jack L. Goldsmith, Customary International Law as Federal

Common Law: A Critique of the Modern Position, 110 HARV.

L. REV. 815, 849 (1997) (the “statement in The Paquete

Habana that CIL [customary international law] was ‘part of

our law’” was “made under the rubric of general common

law” and “did not mean that CIL had the status of federal

law”); Ernest A. Young, Sorting Out the Debate over

Customary International Law, 42 VA. J. INT’L L. 365, 393-94

(2002) (“as virtually all participants in the customary law

debate agree,” before Erie, international law “had the status of

‘general’ law: neither state nor federal”); Bradford R. Clark,

Federal Common Law: A Structural Reinterpretation, 144 U.

PA. L. REV. 1245, 1279-81 & n.169 (1996) (before Erie,

international law, including the laws governing war,

“operated as a set of background rules that courts applied in

17

the absence of any binding sovereign command to the

contrary”); John F. Manning, Textualism and the Equity of the

Statute, 101 COLUM. L. REV. 1, 99 n.382 (2001) (“Because

courts applying the law of nations believed that they were

merely implementing a pre-existing body of customary law,

this decisionmaking process was not conceived of as

lawmaking per se.”).

But as decided by the Supreme Court in its landmark Erie

decision in 1938, the view that federal courts may ascertain

and enforce international-law norms as part of the general

common law is fundamentally inconsistent with a proper

understanding of the role of the Federal Judiciary in our

constitutional system. In Erie, the Supreme Court famously

held that there is no general common law enforceable by

federal courts. Erie, 304 U.S. at 78. The Court said that “law

in the sense in which courts speak of it today does not exist

without some definite authority behind it.” Id. at 79

(quotation omitted).

Erie means that, in our constitutional system of separated

powers, federal courts may not enforce law that lacks a

domestic sovereign source. Erie “requires federal courts to

identify the sovereign source for every rule of decision,” and

the “appropriate ‘sovereigns’ under the U.S. Constitution are

the federal government and the states.” Bradley &

Goldsmith, Customary International Law, 110 HARV. L. REV.

at 852; see also Anthony J. Bellia Jr., State Courts and the

Making of Federal Common Law, 153 U. PA. L. REV. 825,

891 (2005) (“the rise of positivistic legal thought led courts to

conclude that all law . . . must be attributable to a sovereign

source”); Louise Weinberg, The Curious Notion that the

Rules of Decision Act Blocks Supreme Federal Common Law,

83 NW. U. L. REV. 860, 867 (1989) (“post-Erie positivism has

18

cleansed American courts of law lacking an identifiable

sovereign source”).5

Some respected scholars have asserted that even though

Erie did away with the idea of federal general common law,

principles of customary international law may still be

recognized as federal common law by federal courts. See,

e.g., Harold Hongju Koh, Is International Law Really State

Law?, 111 HARV. L. REV. 1824, 1835 (1998). But that notion

is very difficult to square with Erie – as other leading scholars

have maintained. Indeed, “[c]ourts and scholars generally

agree that federal common law must be authorized in some

fashion by the Constitution or a federal statute.” Bradley &

Goldsmith, Customary International Law, 110 HARV. L. REV.

at 856; see also Martha A. Field, Sources of Law: The Scope

5

Amici cite several cases in which, they say, “the Supreme

Court has relied upon the laws of war as default rules governing the

conduct of hostilities, applicable absent explicit statutory language

to the contrary.” Br. for Non-Governmental Orgs. & Scholars as

Amici Curiae in Supp. of Reh’g or Reh’g En Banc at 4-5. With one

exception, the cases cited date from the pre-Erie era when

international-law norms were regarded as part of the general

common law discoverable and enforceable by federal courts. Those

cases are not controlling after Erie. Cf. Daniel J. Freeman, The

Canons of War, 117 YALE L.J. 280, 319 (2007) (“[A]s domestic

perception of international law has evolved from being ‘part of our

law’ to a patchwork of ambitious declarations and treaties riddled

with reservations, courts ceased to constrain the breadth of AUMFs

by reference to international law. . . . [A]voidance of international

law – independent of domestic implementation – has not affected

interpretation of an AUMF in a hundred years.”). Only one cited

case – Ex parte Quirin – post-dates Erie. And Quirin supports,

rather than undermines, the framework outlined in this opinion.

That case involved two statutes (Articles of War 12 and 15) that

expressly referenced and thereby incorporated the “law of war.”

See 317 U.S. at 27.

19

of Federal Common Law, 99 HARV. L. REV. 881, 887 (1986)

(a court “must point to a federal enactment, constitutional or

statutory, that it interprets as authorizing the federal common

law rule”); Henry J. Friendly, In Praise of Erie – and of the

New Federal Common Law, 39 N.Y.U. L. REV. 383, 407

(1964) (federal common law limited to “areas where

Congress, acting within powers granted to it, has manifested,

be it ever so lightly, an intention to that end”).

In light of Erie, it follows that “the wholesale

incorporation of customary international law as federal

common law . . . . offends constitutional norms of federalism,

separation of powers, and democracy,” because such

incorporation would “allow courts to recognize federal norms

that do not derive from any of the lawmaking procedures

specified by the Constitution.” Young, Sorting Out the

Debate, 42 VA. J. INT’L L. at 462.6

In any event, no matter how one might previously have

approached the debate about the post-Erie status of customary

international law, the Supreme Court’s 2004 decision in Sosa

resolved it. See 542 U.S. 692. The Court rejected the notion

6

The Supreme Court has recognized that federal courts retain

authority post-Erie to craft and apply what is sometimes referred to

as “federal common law” in those areas in which courts have

“express congressional authorization to devise a body of law,” as

well as a few “interstitial areas of particular federal interest.” Sosa,

542 U.S. at 726; see also O’Melveny & Myers v. FDIC, 512 U.S.

79, 87 (1994); Boyle v. United Techs. Corp., 487 U.S. 500, 504-06

(1988). For example, Federal Rule of Evidence 501 expressly

authorizes federal courts to recognize evidentiary privileges

according to “the principles of the common law as they may be

interpreted by the courts of the United States in the light of reason

and experience.” See, e.g., Univ. of Penn. v. EEOC, 493 U.S. 182,

188-89 (1990).

20

that all customary-international-law norms are independently

enforceable in federal court. See id. at 728. The Court

decided that, post-Erie, federal courts could recognize claims

under the Alien Tort Statute for violation of a narrowly

defined subset of international-law norms – not on the theory

that international law is automatically incorporated into U.S.

law, but rather only to give effect to the congressional intent

underlying the ATS’s grant of jurisdiction in 1789. See id. at

724, 729-30, 731 n.19, 732.

Sosa thus confirmed that international-law principles are

not automatically part of domestic U.S. law and that those

principles can enter into domestic U.S. law only through an

affirmative act of the political branches. After all, if

customary international law is automatically federal law, then

the ATS “ought to cover all CIL claims, so long as they also

qualify as torts. But Sosa rejected this view” and instead

“gave domestic legal force to an extremely limited subset of

CIL claims . . . based on its reading of the specific intent of

Congress.” Ernest A. Young, Sosa and the Retail

Incorporation of International Law, 120 HARV. L. REV. F. 28,

29 (2007). The Sosa Court mandated, in other words, “that

any federal common law relating to CIL be grounded in,

conform to, and not exceed the contours of what the political

branches have authorized.” Curtis A. Bradley, Jack L.

Goldsmith & David H. Moore, Sosa, Customary International

Law, and the Continuing Relevance of Erie, 120 HARV. L.

REV. 869, 902 (2007). The Court’s insistence on that point

“simply cannot be reconciled” with the position that “all of

CIL is automatically part of judge-made federal common law

even in the absence of political branch authorization.” Id.

Sosa therefore “would seem to preclude binding the President

to CIL as a matter of domestic law in the absence of an

incorporating statute or treaty.” Id. at 930-31; cf. In re XE

Servs. Alien Tort Litigation, 665 F. Supp. 2d 569, 579 (E.D.

21

Va. 2009) (“It is clear, then, that Sosa does not incorporate

customary international law . . . into the body of federal

common law in a wholesale manner.”).

C

Al-Bihani cites various international-law norms to

challenge his detention. But Al-Bihani does not invoke any

principles that are actually part of domestic U.S. law

enforceable in U.S. courts. He cites no controlling statutes (or

executive regulations) or self-executing treaties to support his

arguments.

Al-Bihani points to a number of purported international-

law principles: (i) that military detention must terminate at the

conclusion of the specific conflict of capture; (ii) that the

capturing government must either afford a detainee prisoner-

of-war status or have the detainee’s status determined by a

competent tribunal; (iii) that an individual who is not a

member of a nation’s armed forces (including one who takes

up arms as part of a volunteer militia) remains a civilian; (iv)

that military force, including detention, cannot be used against

civilians unless and until they engage in activities constituting

“direct participation in hostilities”; and (v) that a party cannot

become a co-belligerent in a particular international armed

conflict unless the party has notice of the conflict and violates

a duty of neutrality with respect to that conflict.

Based on these and other international-law principles, Al-

Bihani also contends, among other things, that supporters of

al Qaeda or the Taliban cannot be detained unless they engage

in activities constituting “direct participation” in hostilities.

The sources on which Al-Bihani relies for those

international-law arguments fall into two distinct categories.

22

First, Al-Bihani cites two treaties to which the United States

is a party: the Third and Fourth Geneva Conventions of 1949,

which were made by President Truman in 1949 and concurred

in by the Senate in 1955. These Conventions were

multilateral treaties made in 1949, originally signed by about

60 nations, and later joined by almost all nations. Second, Al-

Bihani cites a variety of other international-law sources: the

1977 Additional Protocols to the Geneva Conventions (which

were signed by the United States under President Carter but

never concurred in by the Senate), commentary from the

International Committee of the Red Cross, and the writings of

various international-law scholars.

None of the sources on which Al-Bihani relies is part of

domestic U.S. law.

Al-Bihani cannot invoke the 1949 Geneva Conventions

as a source of domestic U.S. law enforceable in federal court

for either of two alternative reasons.

To begin with, the 1949 Geneva Conventions are not

self-executing treaties and thus are not domestic U.S. law. To

reiterate, a self-executing treaty is one whose terms “reflect a

determination by the President who negotiated it and the

Senate that confirmed it that the treaty has domestic effect.”

Medellín, 552 U.S. at 521. A treaty is non-self-executing

when it “reads like a compact between independent nations

that depends for the enforcement of its provisions on the

interest and the honor of the governments which are parties to

it.” Id. at 508-09 (quoting Head Money Cases, 112 U.S. at

598) (internal quotation marks omitted).

Under that test, the 1949 Geneva Conventions are non-

self-executing treaties. Common Article 1 of the 1949

Geneva Conventions provides: “The High Contracting Parties

23

undertake to respect and to ensure respect for the present

Convention in all circumstances.” That language is very

similar to the language found in Article 94 of the United

Nations Charter, which the Supreme Court recently held to be

non-self-executing. Article 94 provides: “Each Member of

the United Nations undertakes to comply with the decision of

the International Court of Justice in any case to which it is a

party.” U.N. Charter art. 94, para. 1 (emphasis added). In

Medellín, the Supreme Court concluded that use of the phrase

“undertakes to comply” – rather than “‘shall’ or ‘must’

comply” – indicated that “further action to give effect to an

ICJ judgment was contemplated” and therefore that the treaty

did not “vest ICJ decisions with immediate legal effect in

domestic courts.” 552 U.S. at 508-09 & n.5. For that reason,

the Medellín Court determined that Article 94 of the U.N.

Charter was non-self-executing.

Under the Medellín analysis, the 1949 Geneva

Conventions’ use of “undertake to respect,” rather than

“shall” or “must” respect, likewise means that “further

action . . . was contemplated” to give the Conventions

domestic effect. Id. at 509 n.5. Like Article 94, therefore, the

1949 Geneva Conventions are not self-executing.

Precedent confirms that the 1949 Geneva Conventions

are non-self-executing. In Johnson v. Eisentrager, 339 U.S.

763 (1950), the Supreme Court analyzed the 1929 version of

the Third Geneva Convention. The Court recognized that

although the Convention granted certain rights to captured

alien enemies in wartime, its “obvious scheme” was that those

rights depended for their enforcement on “political and

military authorities” and that they could be

“vindicated . . . only through protests and intervention of” the

national governments that were parties to the Convention – in

other words, that the 1929 Geneva Convention was non-self-

24

executing. Id. at 789 n.14; see also Holmes v. Laird, 459 F.2d

1211, 1222 (D.C. Cir. 1972) (Eisentrager found the

“corrective machinery specified in” the 1929 Convention to

be “nonjudicial”).

The Supreme Court’s description of the 1929 Convention

also accurately characterizes the text of the 1949 Geneva

Conventions and supports the conclusion that the 1949

Conventions are non-self-executing. Indeed, our Court

previously ruled as much in an opinion that is not precedential

but is nonetheless persuasive on this point. See Hamdan v.

Rumsfeld, 415 F.3d 33, 39 (D.C. Cir. 2005) (“There are

differences, but none of them renders Eisentrager’s

conclusion about the 1929 Convention inapplicable to the

1949 Convention.”), rev’d on other grounds, 548 U.S. 557

(2006); see also Hamdi v. Rumsfeld, 316 F.3d 450, 468 (4th

Cir. 2003) (“what discussion there is of enforcement [in the

1949 Geneva Conventions] focuses entirely on the vindication

by diplomatic means of treaty rights inhering in sovereign

nations”), vacated and remanded on other grounds, 542 U.S.

507 (2004).

In sum, although the 1949 Geneva Conventions “create[]

an international law obligation on the part of the United

States,” they do not of their “own force constitute binding

federal law.” Cf. Medellín, 552 U.S. at 522. The political

branches may incorporate principles found in the Geneva

Conventions into domestic U.S. law, as they have done on

various occasions. See, e.g., 18 U.S.C. § 2441 (prohibiting

grave breaches of the 1949 Geneva Conventions such as rape,

torture, and murder). So, too, the Executive Branch, acting

within the bounds of its statutory and constitutional authority,

may adhere to the Geneva Conventions as a matter of

international obligation or policy. But because the

25

Conventions are not self-executing, a court cannot compel

compliance with the Geneva Conventions in this context.

But even assuming arguendo that the 1949 Geneva

Conventions were self-executing as written and ratified,

Congress has since unambiguously repudiated whatever

domestic legal effect the Conventions otherwise might have

had in this habeas setting. Section 5(a) of the Military

Commissions Act of 2006 – a provision that was left intact by

the Military Commissions Act of 2009 – provides in broad

and plain terms: “No person may invoke the Geneva

Conventions or any protocols thereto in any habeas corpus or

other civil action or proceeding to which the United States, or

a current or former officer, employee, member of the Armed

Forces, or other agent of the United States is a party as a

source of rights in any court of the United States.” Pub. L.

No. 109-366, § 5(a), 120 Stat. 2600, 2631. The decision by

the United States to repudiate any judicially enforceable effect

of the 1949 Geneva Conventions in this context resulted from

the considered judgment of two Congresses and two

Presidents – as reflected in the original 2006 Act and in the

2009 determination not to disturb that provision of the 2006

Act.

A statute can repeal a self-executing treaty (or the

domestic force of a self-executing treaty), just as a statute can

repeal a prior statute. See Medellín, 552 U.S. at 509 n.5;

Breard v. Greene, 523 U.S. 371, 376 (1998). Consistent with

that principle, § 5(a) of the 2006 Military Commissions Act

has “superseded whatever domestic effect the Geneva

Conventions may have had in actions such as this.” Noriega

v. Pastrana, 564 F.3d 1290, 1296 (11th Cir. 2009), cert.

denied, 130 S. Ct. 1002 (2010). A habeas court may not

invoke the Geneva Conventions against the Executive. As the

panel opinion in this case concluded, the plain text of the

26

Military Commissions Act thus precludes Al-Bihani from

relying on the Geneva Conventions in this habeas context.

In a footnote in his rehearing petition, Al-Bihani says that

§ 5(a) of the Military Commissions Act of 2006 “does not

apply to his petition, both as a matter of statutory language

and general retroactivity principles” and that applying it

“would violate the Suspension Clause.” Al-Bihani Pet. for

Reh’g and Reh’g En Banc at 7 n.5. Those arguments have no

merit.

Al-Bihani’s assertion that § 5(a) does not apply to his

petition “as a matter of statutory language” is incorrect. As

already explained, the “statutory language” of § 5(a) plainly

eliminates any domestic effect the Geneva Conventions might

have had in habeas cases, as the Eleventh Circuit correctly

held. See Noriega, 564 F.3d at 1296. In other words, to the

extent the Conventions were once self-executing, “Congress

has effectively unexecuted [them],” at least for habeas matters

of this kind. Curtis A. Bradley, The Military Commissions

Act, Habeas Corpus, and the Geneva Conventions, 101 AM. J.

INT’L L. 322, 341 (2007).

Nor does applying § 5(a) to this dispute pose a

retroactivity problem. The relief Al-Bihani seeks is purely

prospective. He asks that we order his release from military

custody on the ground that his continued, future detention

would be unlawful. “When [an] intervening

statute . . . affects the propriety of prospective relief,

application of the new provision is not retroactive.” Landgraf

v. USI Film Prods., 511 U.S. 244, 273 (1994); see also id. at

293 (Scalia, J., concurring in judgment) (“Since the purpose

of prospective relief is to affect the future rather than remedy

the past, the relevant time for judging its retroactivity is the

very moment at which it is ordered.”). Whether § 5(a) would

27

apply retroactively to a civil case in which a plaintiff sought

damages for injuries predating enactment of the 2006 MCA is

a question we need not address here.

Al-Bihani’s Suspension Clause argument is likewise

meritless. Section 5(a) does not implicate the Suspension

Clause because it does not suspend the jurisdiction of the

federal courts to hear habeas challenges by detainees such as

Al-Bihani. Rather, by repealing the domestic effect of the

Geneva Conventions in this context, § 5(a) simply addresses

the substantive law that courts may apply to resolve habeas

petitions. See Noriega, 564 F.3d at 1294 (§ 5(a) does not bar

petitioners “from seeking habeas relief,” but merely “changes

one substantive provision of law upon which a party might

rely in seeking habeas relief”); cf. INS v. St. Cyr, 533 U.S. 289

(2001).

Apart from the 1949 Geneva Conventions, Al-Bihani

does not rely on any treaties (either self-executing or non-self-

executing) that have been made by the U.S. President with the

concurrence of two-thirds of the U.S. Senate. The other

international-law sources he cites – the 1977 Additional

Protocols to the Geneva Conventions, Red Cross

commentaries, and writings of international-law scholars –

may reflect or give rise to principles of customary

international law. And those customary-international-law

principles may in turn impose obligations on (or raise policy

considerations for) the United States in its international

relations. The political branches thus may decide to adhere to

those international-law norms. But absent incorporation into

a statute or a self-executing treaty, such customary-

28

international-law principles are not part of the domestic law

of the United States that is enforceable in federal court.7

* * *

To sum up where we are so far: International-law

principles are not automatically part of domestic U.S. law

enforceable in federal courts. Congress and the President may

incorporate international-law principles into domestic U.S.

law via a statute (or binding executive regulation) or a self-

executing treaty; and when they do so, federal courts will

afford that statute or self-executing treaty the full respect

7

Even if international law were a judicially enforceable

constraint on the President’s authority under the AUMF and even if

international law prohibited detention of mere supporters of al

Qaeda, Al-Bihani’s argument that al Qaeda supporters cannot be

detained would be unavailing. An enemy belligerent may be

detained for the duration of these hostilities. See Hamdi, 542 U.S.

at 518 (plurality opinion of O’Connor, J.) (interpreting scope of

AUMF’s detention authority). And in the Military Commissions

Act of 2006 and the Military Commissions Act of 2009, Congress

provided that the category of enemy belligerents includes those

who “purposefully and materially supported hostilities against the

United States or its coalition partners.” See MCA of 2006 sec.

3(a)(1), § 948a(1)(A)(i), 120 Stat. at 2601; MCA of 2009, Pub. L.

No. 111-84, tit. 18, sec. 1802, § 948a(7)(B), 123 Stat. 2574, 2575

(codified at 10 U.S.C. § 948a(7)(B)). A statute may of course

override pre-existing statutes, including any statutes that

incorporate international law. Therefore, as the panel opinion

explained, the Military Commissions Act definitively establishes

that those who purposefully and materially support al Qaeda may

be detained for the duration of the hostilities, regardless of what

international law might otherwise say about detention of such

supporters. See Al-Bihani v. Obama, 590 F.3d 866, 872 (D.C. Cir.

2010); contra Hamlily v. Obama, 616 F. Supp. 2d 63, 76 (D.D.C.

2009).

29

ordinarily due to federal statutes. But international-law norms

that are not incorporated into either a statute or a self-

executing treaty – including norms reflected in the 1949

Geneva Conventions and the other international-law sources

relied on by Al-Bihani – do not have the status of domestic

U.S. law enforceable in federal courts.

II

Even though none of the international-law sources Al-

Bihani relies on is part of domestic U.S. law, Al-Bihani and

amici alternatively argue that courts must nonetheless apply

international-law principles in resolving cases under the 2001

Authorization for Use of Military Force, Pub. L. No. 107-40,

115 Stat. 224. In particular, Al-Bihani and amici contend that

we should interpret the AUMF as incorporating international-

law principles that limit the President’s authority under the

AUMF to wage war against al Qaeda and the Taliban.

On its face, this is a radical argument. Al-Bihani and

amici would have the Federal Judiciary limit the scope of the

President’s war-making authority – not based on the

Constitution and not based on express language in a statute or

self-executing treaty, but rather based on international-law

norms that have never been enacted into domestic U.S. law by

American lawmakers.

For the reasons set forth at length below, the argument

advanced by Al-Bihani and amici lacks merit: Congress has

broadly authorized the President to wage war against al Qaeda

and the Taliban. Neither the AUMF’s text nor its legislative

history suggests that Congress intended international-law

principles to limit the scope of that congressional

authorization. Congress often incorporates international-law

principles into federal law; it did not do so here. Courts must

30

respect that decision. Congress has also enacted a vast body

of domestic U.S. laws of war. But Congress has provided no

indication that it wants courts to freelance and go beyond

Congress’s direction by imposing international-law limits on

the Executive. Moreover, the Charming Betsy canon of

statutory construction does not authorize courts to read

international-law limitations into the authority granted to the

President by the AUMF. The Supreme Court’s decision in

Hamdi v. Rumsfeld, 542 U.S. 507 (2004), similarly does not

support Al-Bihani’s submission.

A

Interpretation of a statute begins (and often ends) with its

text. See Exxon Mobil Corp. v. Allapattah Servs., Inc., 545

U.S. 546, 567-68 (2005); Lamie v. U.S. Trustee, 540 U.S. 526,

534 (2004); Hughes Aircraft Co. v. Jacobson, 525 U.S. 432,

438 (1999).

The text of the 2001 AUMF provides in broad terms:

[T]he President is authorized to use all necessary and

appropriate force against those nations,

organizations, or persons he determines planned,

authorized, committed, or aided the terrorist attacks

that occurred on September 11, 2001, or harbored

such organizations or persons, in order to prevent

any future acts of international terrorism against the

United States by such nations, organizations or

persons.

§ 2(a), 115 Stat. at 224.

The AUMF specifies the enemies against whom the

President is authorized to use force – namely, those nations,

31

organizations, or persons the President deems to have

sufficient connection to the September 11th attacks.8 The

AUMF affords the President broad discretion with respect to

methods of force, use of military resources, timing, and

choice of targets – except, of course, to the extent the U.S.

Constitution or other federal statutes or self-executing treaties

independently limit the President. In those respects, the

AUMF resembles several prior American war declarations

and authorizations, such as those during World War II. See,

e.g., Joint Resolution of Dec. 8, 1941, ch. 561, 55 Stat. 795

(“the President is hereby authorized and directed to employ

the entire naval and military forces of the United States and

the resources of the Government to carry on war against the

Imperial Government of Japan”); Joint Resolution of Dec. 11,

1941, ch. 564, 55 Stat. 796 (same language, substituting

“Government of Germany”); see also Curtis A. Bradley &

Jack L. Goldsmith, Congressional Authorization and the War

on Terrorism, 118 HARV. L. REV. 2047, 2083 (2005) (the

2001 AUMF “is as broad as authorizations in declared wars

with respect to the resources and methods it authorizes the

President to employ, and with respect to the purposes for

which these resources can be used”).9

8

Under the language of the AUMF, al Qaeda is a permissible

target for the use of military force because President Bush

determined that al Qaeda had planned and committed the

September 11th attacks. Similarly, the Taliban is a permissible

target under the AUMF because President Bush determined that the

Taliban had harbored al Qaeda in Afghanistan.

9

The 2001 AUMF is broader than certain other force

authorizations that have limited the scope of authorized presidential

action by regulating the method of force, controlling the use of

military resources, setting limits on the timing, or dictating or

limiting the choice of targets. For example, in November 1993,

Congress authorized the President to use the U.S. Armed Forces in

Somalia, but only through March 1994 and only for two specific,

32

There is no indication in the text of the AUMF that

Congress intended to impose judicially enforceable

international-law limits on the President’s war-making

authority under the AUMF. As explained in Part I of this

opinion, Congress has enacted many statutes – including war-

related statutes – that expressly refer to international law. But

unlike those statutes, the AUMF contains no reference to

international law. That omission is critically important here

because, as the Supreme Court has recognized, “Congress

knows how to accord domestic effect to international

obligations when it desires such a result.” Medellín v. Texas,

552 U.S. 491, 522 (2008). Congress did not do so in the

AUMF. So too, in enacting the general War Powers

Resolution, Congress did not require the President to comply

with all facets of international law when commanding and

directing U.S. war efforts. See 50 U.S.C. §§ 1541-1548.10

The silence strongly suggests that Congress did not

intend to impose judicially enforceable international-law

limited purposes – protecting “United States personnel and bases”

and “securing open lines of communication for the free flow of

supplies and relief operations.” Department of Defense

Appropriations Act, 1994, Pub. L. No. 103-139, § 8151(b), 107

Stat. 1418, 1475-77 (1993).

10

Thus, Al-Bihani’s argument that the President’s detention

authority under the AUMF “derives from” international law is

wrong. Al-Bihani Opening Br. at 38. The President’s detention

authority under the AUMF derives from the text of the statute.

Even in the absence of specific congressional authorization,

moreover, the President’s authority to detain at least non-citizen

enemies captured abroad also independently derives from Article II

of the Constitution, as explained below in Part III of this opinion.

33

constraints on the President’s war-making authority, including

on his detention authority.11

11

Some have suggested that Congress’s use of the phrase “all

necessary and appropriate force” in the AUMF signaled an implicit

intent to bind the President to international-law norms, apparently

on the theory that any act in violation of those norms would not be

“appropriate.” See, e.g., JORDAN J. PAUST, BEYOND THE LAW: THE

BUSH ADMINISTRATION’S UNLAWFUL RESPONSES IN THE “WAR”

ON TERROR 92 (2007); Ingrid Brunk Wuerth, Authorizations for the

Use of Force, International Law, and the Charming Betsy Canon,

46 B.C. L. REV. 293, 325-26 (2005). That interpretation is

fundamentally at odds with how that and similar phrases have been

understood in American law.

For example, the U.S. Constitution endows Congress with

power to “make all Laws which shall be necessary and proper for

carrying into Execution” the “Powers vested by this Constitution in

the Government of the United States.” Art. I, § 8, cl. 18. For

nearly two centuries, the Supreme Court has interpreted the

Necessary and Proper Clause as giving Congress “broad power to

enact laws” that need only be “rationally related to the

implementation of a constitutionally enumerated power.” United

States v. Comstock, 130 S. Ct. 1949, 1956 (2010); see McCulloch v.

Maryland, 17 U.S. 316, 420-21 (1819).

Moreover, in the field of federal administrative law, Congress

has enacted numerous statutes authorizing agency action that is

“necessary and appropriate” to a certain end. See, e.g., 7 U.S.C.

§ 2(a)(1)(E)(i) (CTFC and SEC may issue certain “necessary and

appropriate” rules); 14 U.S.C. § 182(a) (Secretary of Homeland

Security “shall take such action as may be necessary and

appropriate to insure that” the Coast Guard does not discriminate

against women); 16 U.S.C. § 1382(a) (Secretary of Commerce shall

prescribe certain “necessary and appropriate” regulations). Courts

generally have interpreted such language as granting agencies

significant discretion. See, e.g., Turtle Island Restoration Network

v. Nat’l Marine Fisheries Serv., 340 F.3d 969, 976-77 (9th Cir.

2003); Madison-Hughes v. Shalala, 80 F.3d 1121, 1128 (6th Cir.

1996).

34

Rather, in ascertaining what the AUMF authorizes, courts

presume that Congress authorized the President, except to the

extent otherwise prohibited by the Constitution or statutes, to

take at least those actions that U.S. Presidents historically

have taken in wartime – including killing, capturing, and

detaining the enemy. See Dames & Moore v. Regan, 453 U.S.

654, 686 (1981) (when an Executive practice is “known to

and acquiesced in by Congress” over an extended period,

“Congress may be considered to have consented to the

President’s action”) (quotation omitted); Haig v. Agee, 453

U.S. 280, 293-303 (1981) (finding “congressional

acquiescence” in longstanding Executive practice of

withholding passports for national security reasons); United

In light of this deeply rooted interpretive tradition, the words

“necessary and appropriate” in the AUMF – far from suggesting a

significant limitation on the President’s war powers – are more

naturally read as emphasizing the breadth of the authorization. See

Bradley & Goldsmith, Congressional Authorization, 118 HARV. L.

REV. at 2081 (“It seems unlikely that Congress, which views the

Necessary and Proper Clause expansively, and has the most to gain

from a broad interpretation of the clause, would have used the

phrase ‘necessary and appropriate’ as a way to constrain

presidential authority.”); cf. Bragdon v. Abbott, 524 U.S. 624, 645

(1998) (Congress legislates against the background of how certain

language has previously been interpreted by the other branches of

government); Lorillard v. Pons, 434 U.S. 575, 580-81 (1978)

(same).

In any event, even if there were some reason to think that

Congress intended the words “necessary and appropriate” to

operate as a significant limit on the President’s discretion, there is

zero reason to conclude that Congress intended for international-

law norms to define the term “appropriate.” It is much more

plausible to think that Congress intended to underscore that the

President must operate within the confines of other U.S. laws

passed by Congress. See infra Part II.C.

35

States v. Midwest Oil Co., 236 U.S. 459, 474 (1915) (“the

long-continued practice [of the President], known to and

acquiesced in by Congress, would raise a presumption . . . of

its consent”); id. at 473 (“in determining the meaning of a

statute . . . weight shall be given to the usage itself”).

B

Even assuming arguendo that the text of the AUMF is

ambiguous on this point – which it is not – the statute’s

legislative history provides no hint that Congress intended to

impose judicially enforceable international-law limitations on

the President’s war-making authority, or on his lesser-

included detention authority. Cf. Allapattah Servs., 545 U.S.

at 568 (legislative history matters at most to the extent it

sheds “a reliable light on the enacting Legislature’s

understanding of otherwise ambiguous terms”). On the

contrary, the House and Senate debates on the AUMF,

although necessarily brief given the urgent timing, contain

numerous statements indicating that Members of Congress

meant to grant the President broad authority in waging a

congressionally approved war. For example:

 “[T]he resolution before us . . . . gives the President

flexibility as Commander in Chief to conduct military

operations as he sees fit.” 147 CONG. REC. 17,116

(2001) (statement of Rep. Hinojosa).

 “[W]e are giving the President the power to conduct a

war.” Id. (statement of Rep. Hunter).

 “[A]s the Commander in Chief, he should and does

have the power to put our American force to the best

use possible across the world.” Id. at 17,129

(statement of Rep. Gekas).

36

 “Under our Constitution, the President of the United

States is commander in chief. When America is

attacked, he assumes the obligations of the

commander in chief.” Id. at 17,138 (statement of

Rep. Lofgren).

 “The resolution . . . reinforces and supports the

powers granted to the President in the Constitution as

Commander in Chief.” Id. at 17,145 (statement of

Rep. Levin).

 “This resolution gives the President the power to

conduct a war without reporting to or consulting with

Congress.” Id. at 17,151 (statement of Rep. Stark).

 “Let us give our Commander in Chief all necessary

authority to put power behind our purpose . . . .” Id.

at 17,041 (statement of Sen. McCain).

 “The [AUMF] permits the President wide latitude to

use force against the broad range of actors who were

responsible for the September 11 attacks.” Id. at

17,047 (statement of Sen. Biden).

These statements and others like them reinforce the

AUMF’s plain text and do not indicate that Congress intended

to incorporate international-law principles as judicially

enforceable limitations on the President’s wartime authority.12

12

A statement by Representative Clayton of North Carolina

has occasionally been cited as evidence that Congress meant to

impose international-law limits on the President’s authority under

the AUMF. Such reliance is mistaken. Representative Clayton

stated: “The authorization we give the President today is not

37

In striking contrast to the lack of references to

international law in the congressional debates on the AUMF,

many in Congress did express their intent that the President

act in accordance with the Constitution and extant and future-

enacted U.S. statutes. For example:

 “America is based on a Constitution and our

laws. . . . Nothing in the resolution supersedes any

requirement of the War Powers Act.” Id. at 17,123

(statement of Rep. DeFazio).

 “We must carry out military action within the

parameters of the Constitution and the War Powers

Act, as this resolution provides.” Id. at 17,125

(statement of Rep. Price).

 “I’m not willing to give President Bush carte blanche

authority to fight terrorism. We need to agree to fight

it together within traditional constitutional

boundaries.” Id. at 17,148 (statement of Rep.

Jackson).

unlimited. Congress will monitor progress of our military actions

and work with the President to ensure that our actions under this

resolution are necessary and appropriate, consistent with our values,

in conjunction with our friends and allies, and in accordance with

international laws.” 147 CONG. REC. 17,146. Representative

Clayton’s statement on its face reflects only a desire for Congress

to “work with the President” in the future to ensure compliance

with international law; it did not in any way suggest that the

authority granted in the AUMF was subject to judicially

enforceable international-law limits. And no other statement in the

legislative record suggested that Members of Congress intended the

AUMF to incorporate judicially enforceable international-law

limits.

38

 “I want those responsible for these heinous crimes to

be hunted down and held accountable – in full

compliance with our Constitution and our laws.” Id.

at 17,150 (statement of Rep. McGovern).

 “This joint resolution is based upon and is an exercise

of the Congress’ constitutional war powers role as

codified in the War Powers Resolution. It also

expressly confirms the conditions on the exercise of

Executive power under that resolution.” Id. at 17,040

(statement of Sen. Levin).

 “[W]e must act within the confines of the

Constitution and the law. I believe that the resolution

before us achieves that goal. . . . When we abide by

our Constitution and our law, we are as strong as we

possibly can be, and we are far stronger than the

malevolent force that we soon will engage.” Id. at

17,041-43 (statement of Sen. Feingold).

The legislative debates preceding passage of the AUMF

show that Congress intended the President to comply with the

Constitution and domestic U.S. law when waging war. But

the debates offer “no suggestion that Congress intended to

impose affirmative CIL [customary international law]

constraints on the President, much less judicially enforceable

CIL constraints.” Curtis A. Bradley, Jack L. Goldsmith &

David H. Moore, Sosa, Customary International Law, and the

Continuing Relevance of Erie, 120 HARV. L. REV. 869, 931

(2007).

39

C

As was noted in the legislative debates before passage of

the 2001 AUMF, Congress has enacted a considerable amount

of legislation limiting wartime actions by the Executive and

military. This comprehensive set of domestic U.S. laws of

war demonstrates that Congress knows how to control

wartime conduct by the Executive Branch. And it

underscores the illegitimacy of courts’ unilaterally restraining

the Executive’s war effort with additional international-law

restrictions that Congress and the President have not seen fit

to enact into domestic U.S. law.

When Congress passed the AUMF in 2001, it did so

against the background of an expansive body of domestic

U.S. law prohibiting wartime actions by the Executive that

contravene American values. For example, in the War

Crimes Act, Congress criminalized various wartime atrocities

constituting “grave breaches” of Common Article 3 of the

1949 Geneva Conventions. Congress subsequently clarified

that such breaches include murder (defined as killing a person

“taking no active part in the hostilities”), torture, biological

experimentation, mutilation, rape, and hostage-taking. 18

U.S.C. § 2441(c)(3), (d)(1). Another criminal statute

separately prohibits the commission of torture outside of U.S.

territory, including by members of the U.S. military. Id. §

2340A. Likewise, in the Genocide Convention

Implementation Act, Congress criminalized acts of genocide

intended to “destroy, in whole or in substantial part, a

national, ethnic, racial, or religious group.” Id. § 1091(a).

These kinds of laws are not a new phenomenon. Since

early in the Nation’s history, Congress has enacted legislation

governing the conduct of the Executive and the military in

war. In 1800, Congress passed the Articles for the

40

Government of the Navy, prohibiting (among other things)

murder, theft, plunder, mistreatment of the crew of a captured

vessel, and mistreatment of inhabitants of a port. See Act of

Apr. 23, 1800, ch. 33, § 1, arts. 9, 21, 26-27, 2 Stat. 45, 46,

48. In 1806, Congress enacted the Articles of War to govern

the U.S. Army, prohibiting (among other things) violence

against civilians and malicious destruction of private property.

See Act of Apr. 10, 1806, ch. 20, arts. 32, 54, 2 Stat. 359, 363-

64, 366. In addition, in 1863, Congress passed a statute

expressly enumerating crimes, including murder, rape, and

wounding, that were punishable by court martial when

committed by military personnel in wartime – a prohibition

that was subsequently incorporated into the Articles of War.

Act of Mar. 3, 1863, ch. 75, § 30, 12 Stat. 731, 736; see U.S.

REV. STAT. § 1342, art. 58 (1875).

During the 19th and early 20th Centuries, Congress made

periodic amendments to the Articles of War and the Articles

for the Government of the Navy, and it repeatedly enacted

revised versions of both sets of Articles in their entirety. See

Act of July 17, 1862, ch. 204, § 1, 12 Stat. 600, 600-06

(Articles for the Government of the Navy); U.S. REV. STAT.

§ 1342 (1875) (Articles of War); id. § 1624 (Articles for the

Government of the Navy); U.S. REV. STAT. § 1342 (2d ed.

1878) (Articles of War); id. § 1624 (Articles for the

Government of the Navy); Act of Aug. 29, 1916, ch. 418, § 3,

39 Stat. 619, 650-70 (Articles of War); Act of June 4, 1920,

ch. 227, subch. 2, 41 Stat. 759, 787-812 (Articles of War).

When the United States Code was compiled in 1926, the Code

incorporated both the Articles of War and the Articles for the

Government of the Navy. See 10 U.S.C. §§ 1471-1593

(1926); 34 U.S.C. § 1200 (1926).

In 1950, Congress enacted the Uniform Code of Military

Justice to revise and consolidate the Articles of War and the

41

Articles for the Government of the Navy (as well as the

disciplinary laws of the Coast Guard). See Act of May 5,

1950, ch. 169, 64 Stat. 107. The UCMJ was substantially

revised in 1968 and again in 1983. See Military Justice Act of

1968, Pub. L. No. 90-632, 82 Stat. 1335; Military Justice Act

of 1983, Pub. L. No. 98-209, 97 Stat. 1393.

The UCMJ sets forth a detailed code of conduct for the

military. Among other things, the UCMJ – like the Articles it

replaced – prohibits members of the U.S. Armed Forces from

committing murder, manslaughter, or rape. 10 U.S.C. §§ 918-

920. Those provisions apply to U.S. soldiers’ conduct in war,

including both conduct directed toward civilians and conduct

directed toward enemy belligerents outside of actual

hostilities. For example, in 1973 the Army Court of Military

Review upheld the court-martial conviction of First

Lieutenant William L. Calley, Jr. under the UCMJ for the

murder of “unarmed, unresisting” Vietnamese villagers at My

Lai. United States v. Calley, 46 C.M.R. 1131, 1165

(A.C.M.R. 1973).

Similarly, the UCMJ prohibits U.S. military personnel

from engaging in “cruelty toward, or oppression or

maltreatment of, any person subject to [their] orders,”

including captured enemy personnel. 10 U.S.C. § 893. The

Court of Appeals for the Armed Forces has held that the

UCMJ imposes on U.S. service members an “affirmative duty

to protect the detainees under [their] charge from abuse,”

which duty is “not affected by” the detainees’ “international

legal status.” United States v. Graner, 69 M.J. 104 (C.A.A.F.

2010) (upholding court-martial conviction under UCMJ for

maltreatment of detainees at military facility in Abu Ghraib,

Iraq); see also United States v. Harman, 68 M.J. 325

(C.A.A.F. 2010) (same); United States v. Smith, 68 M.J. 316

(C.A.A.F. 2010) (same).

42

The UCMJ also guarantees a number of procedural and

substantive rights to prisoners of war who are accused of

crimes and tried before courts martial. Those rights include

appointment of counsel, equal opportunity to obtain witnesses

and evidence, judicial review, and protection against

compulsory self-incrimination, double jeopardy, and cruel and

unusual punishment. See 10 U.S.C. §§ 802(a)(9), (13), 818,

831, 838, 844, 846, 855, 867-867a, 870.

In addition to those statutes regulating conduct during

war, the War Powers Resolution was enacted by Congress in

1973. In its most pertinent provision, the War Powers

Resolution prohibits the President from deploying U.S.

Armed Forces in hostile situations for more than 62 calendar

days unless Congress specifically authorizes the deployment.

See 50 U.S.C. §§ 1543(a), 1544(b).13

Since passage of the AUMF in 2001, Congress has

enacted additional legislation regulating the Executive’s

conduct of the war. These statutes reveal that Congress has

repeatedly responded with new legislation addressing some of

the unique issues posed by a war against a non-uniformed

enemy. These statutes further demonstrate that Congress

knows how to legislate war-related restrictions on the

Executive – and does not need or intend for the courts to

impose new international-law-based restrictions. For

example, as part of the Detainee Treatment Act of 2005,

Congress provided in broad terms that “[n]o individual in the

custody or under the physical control of the United States

Government, regardless of nationality or physical location,

13

Many Administrations have questioned the constitutionality

of the War Powers Resolution, but that is not relevant for this

discussion.

43

shall be subject to cruel, inhuman, or degrading treatment or

punishment” and that military detainees in the custody or

control of the Department of Defense shall not be subject to

methods of interrogation not specifically authorized in the

Army Field Manual on Intelligence Interrogation. §§ 1002-

1003, Pub. L. No. 109-148, div. A, tit. 10, 119 Stat. 2739,

2739-40 (codified at 10 U.S.C. § 801 note and 42 U.S.C.

§ 2000dd). And in the Military Commissions Acts of 2006

and 2009, Congress guaranteed unprivileged enemy

belligerents many of the same procedural and substantive

rights the UCMJ affords to prisoners of war. See 10 U.S.C.

§§ 948b(a), 949c(b), 949h, 949j, 949s, 950g, 950h. In the

2006 MCA, Congress also updated the War Crimes Act to

clarify which violations of Common Article 3 of the 1949

Geneva Conventions are punishable as war crimes under

domestic U.S. law. See MCA of 2006, Pub. L. No. 109-366,

sec. 6(b), 120 Stat. 2600, 2633-35 (amending 18 U.S.C.

§ 2441).14

14

The numerous statutory limitations on the wartime actions

of the Executive Branch are supplemented by a variety of legally

binding regulations that the Executive Branch itself has long

promulgated to govern the wartime activities of the U.S. Armed

Forces. In 1863, President Lincoln famously issued General Orders

No. 100, more commonly known as the Lieber Code. See General

Orders No. 100: Instructions for the Government of Armies of the

United States in the Field (Apr. 24, 1863), reprinted in RICHARD

SHELLY HARTIGAN, LIEBER’S CODE AND THE LAW OF WAR 45-71

(1983).

Today, for example, Army Regulation 190-8 governs the

treatment of enemy prisoners of war and other detainees in the

custody of the U.S. Armed Forces. See Enemy Prisoners of War,

Retained Personnel, Civilian Internees and Other Detainees, Army

Reg. 190-8 (Oct. 1, 1997).

When Congress passes a war-authorizing statute like the

AUMF, such regulations – like the statutes described in the text

above – form part of the domestic U.S. law of war background

44

This extensive body of domestic U.S. laws of war shows

that Congress knows how to impose limits on the wartime

conduct of the Executive Branch when it wants to do so. To

the extent Congress has not seen the need to regulate every

last aspect of the President’s waging of war, we can assume

that Congress has confidence in the President’s ability to

exercise his discretion appropriately – and if it loses such

confidence, Congress may act anew to further limit that

presidential discretion, as it has done on numerous occasions.

See Agee, 453 U.S. at 291-92; cf. Chevron U.S.A. Inc. v.

Natural Res. Def. Council, Inc., 467 U.S. 837, 842-45 (1984).

For present purposes, the critical point is this: The significant

body of laws regulating the Executive undermines any

argument that Congress silently intended for U.S. courts to

impose additional limitations on the Executive’s conduct of a

congressionally authorized war effort. That is especially true

with respect to limitations based on international-law norms

that Congress and the President have chosen not to

incorporate into domestic U.S. law.

This expansive collection of domestic U.S. laws of war

also answers Judge Williams’ concern that it “would be an

odd member of Congress who supposed that in authorizing

the use of military force he was embracing uses equivalent to

all such uses that have ever occurred: think Nanking 1937-38;

Katyn 1940; Lidice 1942; My Lai 1968.” Williams Op. at 2-

3. When a war-related practice is truly subject to universal,

worldwide condemnation to the degree Judge Williams seems

against which Congress legislates. To be sure, the Executive is

always free to change its regulations, but the existence of these

longstanding regulations is not irrelevant when attempting to divine

whether Members of Congress in 2001 actually intended for

international law to operate as an additional judicially enforceable

constraint on the President.

45

to contemplate, it typically also contravenes American values,

and Congress and the President in turn have tended to ban the

practice. The historical atrocities Judge Williams invokes,

such as rape, torture, and the killing of civilians, are all

prohibited by the domestic U.S. laws described above.

Notably, Judge Williams points to no examples of violations

of international law that are contrary to fundamental

American values but are not already independently prohibited

by domestic U.S. law.

Contrary to Judge Williams’ implication, however, it has

not been Congress’s stated intent or practice to rely on federal

courts to pick and choose additional international-law

principles to constrain the Executive. Judge Williams cites no

evidence to support his view that Members of Congress

actually intended as much when they voted on September 14,

2001.

D

Up to this point, my argument about the AUMF and

international law has been straightforward: Congress knows

how to regulate U.S. war efforts, and it has done so

extensively on many occasions, creating an elaborate body of

domestic U.S. laws of war. And furthermore, Congress

knows how to reference international law when it so chooses.

The AUMF does not reference international law, nor is there

any indication in the legislative debates of a congressional

intent to incorporate international law into the AUMF.

Therefore, we should interpret the AUMF’s textual silence

with respect to international law as indicative of a

congressional intent not to impose judicially enforceable

international-law limits on the President’s war-making

authority. Under this approach, the default presumption is

that international law is not a judicially enforceable limit on a

46

President’s wartime authority unless Congress expressly says

it is.

Al-Bihani and amici seek to flip that default presumption

by invoking the Charming Betsy canon of statutory

construction. According to their articulation of that canon,

ambiguities in federal statutes must be interpreted in accord

with international-law norms that are not themselves domestic

U.S. law. See Murray v. Schooner Charming Betsy, 6 U.S.

64, 118 (1804); see also RESTATEMENT (THIRD) OF FOREIGN

RELATIONS LAW OF THE UNITED STATES § 114 (1987). Al-

Bihani and amici thus argue that international law is a

judicially enforceable limit on the President’s authority under

a war-authorizing statute unless Congress expressly says it is

not.15

15

When courts construe ambiguous statutes to conform to pre-

existing statutes or self-executing treaties, which are part of

domestic U.S. law, courts are not applying Charming Betsy but

instead are applying a different canon of construction: the familiar

presumption against implied repeal. See Nat’l Ass’n of Home

Builders v. Defenders of Wildlife, 551 U.S. 644, 662-63 (2007) (the

Court “will not infer a statutory repeal” unless Congress’s intention

is clear); Trans World Airlines, Inc. v. Franklin Mint Corp., 466

U.S. 243, 252 (1984) (refusing to find “implicit repeal” of self-

executing treaty in “ambiguous congressional action”).

It is uncontroversial that courts must apply the presumption

against implied repeal when interpreting the AUMF. In Hamdan v.

Rumsfeld, for example, the Supreme Court held that the AUMF did

not impliedly repeal a pre-existing federal statute – Article 21 of the

Uniform Code of Military Justice, 10 U.S.C. § 821 – because

“[r]epeals by implication are not favored.” 548 U.S. 557, 593-95

(2006) (quoting Ex parte Yerger, 75 U.S. 85, 105 (1869)).

But the fact that courts must interpret the AUMF not to

implicitly repeal pre-existing domestic U.S. law obviously does not

mean that courts must interpret the AUMF consistently with

47

Al-Bihani’s argument is flawed for any of three

alternative reasons discussed below in order from broadest to

narrowest. First, after Erie, Sosa, and Medellín, courts should

not invoke the Charming Betsy canon to conform federal

statutes to non-self-executing treaties or customary

international law. Second, even if the Charming Betsy canon

carries weight in some such cases, it is not properly invoked

against the Executive to conform statutes to non-self-

executing treaties or customary international law. Third, even

if use of the Charming Betsy canon is proper against the

Executive in some cases, it is improper when the statute at

issue is a congressional authorization of war.

1

As an initial matter, Al-Bihani’s invocation of Charming

Betsy fails because he wants courts to alter their interpretation

of the AUMF based on non-self-executing treaties and

customary international law.

After Erie, and particularly after the Supreme Court’s

recent decisions in Sosa and Medellín, there is no legitimate

basis for courts to alter their interpretation of federal statutes

to make those statutes conform with non-self-executing

treaties and customary international law, given that those

sources lack any status as domestic U.S. law.

With respect to non-self-executing treaties, there is a

strong inference that Congress deliberately chose not to

incorporate such treaties into domestic U.S. law. Every non-

self-executing treaty to which the United States is a party has

international-law norms that Congress has not incorporated into

domestic U.S. law.

48

been presented to and concurred in by the Senate, as required

by the U.S. Constitution. Thus, courts can presume that

Congress is fully aware of the international commitments and

obligations that such treaties embody. The fact that the

Senate has concurred in a non-self-executing treaty – thereby

making it binding on the United States as a matter of

international law and obligation – but Congress has not

passed a statute to implement the treaty domestically,

indicates that Congress did not want those norms to be part of

domestic U.S. law. It therefore makes sense to conclude that

Congress would not want courts to smuggle those norms into

domestic U.S. law through the back door, by using them as a

basis to alter judicial interpretation of a federal statute. See

Medellín, 552 U.S. at 522 (“Congress knows how to accord

domestic effect to international obligations [in a non-self-

executing treaty] when it desires such a result”); Fund for

Animals, Inc. v. Kempthorne, 472 F.3d 872, 880 (D.C. Cir.

2006) (Kavanaugh, J., concurring).

As to customary international law, the problems with

applying Charming Betsy are equally substantial. There was a

good argument for interpreting statutes in light of customary

international law in the days before Erie, when customary-

international-law principles were considered part of the

general common law that all federal courts could enforce.

See, e.g., John F. Manning, Deriving Rules of Statutory

Interpretation from the Constitution, 101 COLUM. L. REV.

1648, 1680 n.146 (2001) (“To the extent that courts applying

the law of nations believed that they were implementing a

preexisting body of customary law, they may have felt

somewhat greater freedom to exercise such independent

common law powers in relation to statutes.”). After Erie and

particularly after Sosa, however, it is clear that customary-

international-law norms, like non-self-executing treaties, are

not part of domestic U.S. law. Congress has incorporated

49

customary international law into domestic U.S. law on

numerous occasions, including in statutes related to war.

Thus, when Congress does not act to incorporate those norms

into domestic U.S. law, such non-incorporation presumably

reflects a deliberate congressional choice. And it likewise

makes sense to conclude that Congress would not want courts

to smuggle those norms into domestic U.S. law through the

back door by using them to resolve questions of American

law. As the Seventh Circuit has stated, use of the Charming

Betsy canon “so as to effectively incorporate customary

international law into federal statutes when the political

branches of our government may have rejected the

international law at issue seems dubious at best.” Sampson v.

Federal Republic of Germany, 250 F.3d 1145, 1153 (7th Cir.

2001); see also Curtis A. Bradley & Jack L. Goldsmith,

Customary International Law as Federal Common Law: A

Critique of the Modern Position, 110 HARV. L. REV. 815,

871-72 (1997) (affording customary international law its

proper status is arguably inconsistent with the Charming

Betsy canon); Curtis A. Bradley, The Charming Betsy Canon

and Separation of Powers: Rethinking the Interpretive Role of

International Law, 86 GEO. L.J. 479, 536 (1997) (“the

redefinition of federal court power after Erie” “compel[s] re-

examination of” the Charming Betsy canon); Note, The

Charming Betsy Canon, Separation of Powers, and

Customary International Law, 121 HARV. L. REV. 1215,

1221-22 (2008) (“courts arguably violate the separation of

powers when they cabin congressional lawmaking power with

a canon that draws force from a body of law that has no

constitutional origin and does not promote any competing

constitutional value”).16

16

Some maintain that Congress would want a court to alter its

interpretation of a statute based on a non-self-executing treaty or

customary international law. There is no persuasive evidence to

50

support that romantic view of congressional intent. To begin with,

the best – and only reliable – evidence of congressional intent is

what Congress chooses to enact into domestic U.S. law. Because

Congress regularly acts to incorporate principles derived from non-

self-executing treaties and customary international law into

domestic U.S. law, we can assume that it acts deliberately when it

chooses not to do so.

Moreover, recent decades have seen mounting extra-statutory

evidence that “compliance with international law is often not the

political branches’ paramount concern.” Bradley, The Charming

Betsy Canon, 86 GEO. L.J. at 518. To take one recent example: In

Medellín, the Supreme Court recognized that the United States had

an international-law obligation to comply with the International

Court of Justice’s Avena decision holding that certain U.S.

prisoners, including Medellín, were entitled to review and

reconsideration of their convictions and sentences. See 552 U.S. at

504, 508, 520. But Congress did not act on a bill that would have

implemented the Avena decision domestically, and Medellín was

put to death by the State of Texas. See Medellín v. Texas, 129 S.

Ct. 360, 361 (2008) (per curiam) (possibility that Congress might

implement Avena through domestic legislation was “too remote to

justify” a stay of execution, given that Congress had “not

progressed beyond the bare introduction of a bill”); Jeremy

Lawrence, Treaty Violations, Section 1983, and International Law

Theory, 16 SW. J. INT’L L. 1, 23-24 (2010).

Evidence like this – and there is a good deal of it – makes it

difficult to plausibly maintain that courts vindicate any realistic

notion of actual congressional intent by altering their interpretation

of statutes to conform to non-self-executing treaties or customary

international law. Indeed, if anything, there seems to be evidence

that Congress affirmatively distrusts certain international legal

organizations. For example, in 2004, the House of Representatives

passed a resolution stating that it:

(4) deplores –

(A) the misuse of the International Court of

Justice (ICJ) by a plurality of member nations of the

United Nations General Assembly for the narrow

51

After Erie, and particularly after Sosa and Medellín,

courts should not invoke the Charming Betsy canon to

conform federal statutes to non-self-executing treaties and

customary international law. Invocation of the Charming

Betsy canon in such circumstances constitutes an “indirect,

‘phantom’ use of international law” that can “have the same

effect as direct incorporation of international law.” Bradley,

The Charming Betsy Canon, 86 GEO. L.J. at 483. Applying

Charming Betsy to customary international law and non-self-

executing treaties would create an “international law-based,

quasi-constitutional ‘penumbra’ that crowds out and inhibits

congressional lawmaking.” Note, The Charming Betsy

Canon, 121 HARV. L. REV. at 1222; cf. Daniel J. Freeman,

The Canons of War, 117 YALE L.J. 280, 321 (2007) (“If the

international law provision is not clearly enforceable – either

through integration in a statute or express self-execution –

then international law yields. However, if international law is

domestically implemented or clearly self-executing, then the

AUMF should not overrule it . . . .”).

political purpose of advancing the Palestinian

position on matters Palestinian authorities have said

should be the subject of negotiations between the

parties; and

(B) the July 9, 2004 advisory judgment of the

ICJ, which seeks to infringe upon Israel’s right to

self-defense, including under Article 51;

(5) regrets the ICJ’s advisory judgment, which is

likely to undermine its reputation and interfere with a

resolution of the Palestinian-Israeli conflict; [and]

(6) commends the President and the Secretary of

State for their leadership in marshaling opposition to the

misuse of the ICJ in this case[.]

H.R. Res. 713, 108th Cong. (2004).

52

The Supreme Court’s case law since Erie is consistent

with this limited role for international law as a device for

interpreting ambiguous federal statutes. In the seven-plus

decades since the Supreme Court’s landmark 1938 decision in

Erie, the Court has invoked Charming Betsy only

sporadically. It has done so to lend support to a distinct and

far narrower canon of statutory construction: the rule that

absent a clear statement from Congress, federal statutes do not

apply outside the United States. This is often called the

presumption against extraterritoriality. See F. Hoffmann-La

Roche Ltd. v. Empagran S.A., 542 U.S. 155, 164-65 (2004)

(Sherman Act did not apply to foreign effects of price-fixing

conduct); McCulloch v. Sociedad Nacional de Marineros de

Honduras, 372 U.S. 10, 21-22 (1963) (National Labor

Relations Act did not apply to foreign-flag vessel employing

alien seamen); Lauritzen v. Larsen, 345 U.S. 571, 577-78

(1953) (Jones Act did not apply to injuries sustained by alien

seaman aboard foreign-flag vessel in foreign waters).

Those extraterritoriality cases constitute a unique

category. As the Court has recognized, special concerns

counsel against applying domestic U.S. law extraterritorially

because doing so can often conflict with the laws of another

sovereign. In such situations, the presumption against

extraterritoriality serves not just to honor the United States’

international-law obligations as a general matter, but to

“avoid or resolve conflicts between competing laws”

established by two sovereign nations. Lauritzen, 345 U.S. at

582; see also Hoffmann-La Roche, 542 U.S. at 164-65

(presumption “helps the potentially conflicting laws of

different nations work together in harmony”); Sociedad

Nacional, 372 U.S. at 21 (“concurrent application” of U.S.

and foreign law to the same conduct would create a

“possibility of international discord”). The Court’s citation of

Charming Betsy in cases applying the presumption against

53

extraterritoriality does not support invocation of the canon

outside of that narrow context. Cf. Gov’t Cert. Opp. Br. at

12-13, Koyo Seiko Co. v. United States, 543 U.S. 976 (2004)

(Solicitor General arguing that “cases applying Charming

Betsy have . . . involved avoidance of ‘unreasonable

interference with the sovereign authority of other nations’”)

(quoting Hoffman-La Roche, 542 U.S. at 164).17

In short, neither judicial respect for international law nor

available evidence regarding actual congressional intent nor

post-Erie Supreme Court precedent justifies use of the

17

In Weinberger v. Rossi, 456 U.S. 25 (1982), the Court

considered a statute that prohibited employment discrimination

against U.S. citizens on U.S. military bases overseas unless such

discrimination was permitted by “treaty.” Based on a variety of

considerations including precedent, foreign policy implications, and

legislative history, the Court construed the term “treaty” in the

statute to include congressional-executive agreements with foreign

nations, and thus concluded that the statute did not override a prior

congressional-executive agreement with the Philippines. Id. at 28-

36. The Court also cited Charming Betsy in passing, but the case

did not concern a statute’s interaction with customary international

law or a non-self-executing treaty; rather, it concerned a statute’s

interaction with a congressional-executive agreement, the language

of which made the agreement self-executing and thus domestic U.S.

law. See id. at 26-27 & n.2 (agreement was made pursuant to

statute and provided that the “United States Armed Forces in the

Philippines shall fill the needs for civilian employment by

employing Filipino citizens”) (emphasis added); cf. Medellín, 552

U.S. at 508-09. Therefore, although Weinberger may have

implicated the presumption against implied repeal, it did not

concern the application of the Charming Betsy canon to customary

international law or non-self-executing treaties.

54

Charming Betsy canon to conform federal statutes to non-self-

executing treaties or customary international law.18

2

Even if one disagrees with that first point about

Charming Betsy, there is an alternative (and far narrower)

reason why the Charming Betsy canon does not apply to

interpretation of the 2001 AUMF: The Charming Betsy canon

may not be invoked against the Executive to conform statutes

to non-self-executing treaties or customary international law.

The basic reason is that the Executive – not international law

or an international tribunal – possesses the authority in the

first instance to interpret ambiguous provisions in statutes and

to determine how best to weigh and accommodate

international-law principles not clearly incorporated into a

statute.

18

To be sure, a U.S. court interpreting a federal statute or

constitutional provision can look at the reasoning of a foreign or

international tribunal on a similar issue. As Justice Ginsburg

recently pointed out, although “foreign decisions do not rank as

precedent” for U.S. courts, “they could be informative in much the

same way as one might gain knowledge or insight from reading a

law review article.” Ruth Bader Ginsburg, “A decent Respect to

the Opinions of [Human]kind”: The Value of a Comparative

Perspective in Constitutional Adjudication, Address to the

International Academy of Comparative Law (July 30, 2010). A

U.S. court examining and giving “respectful attention” to the

reasoning of a non-U.S. tribunal is, of course, entirely different

from a U.S. court either (i) saying that international law is itself

domestic U.S. law or (ii) altering its interpretation of a statute or

constitutional provision so as to conform domestic U.S. law to

international or foreign law.

55

Since Erie, the Supreme Court has never invoked the

Charming Betsy canon to decide a case against the Executive.

The Ninth Circuit has explained why courts should not do so.

See United States v. Corey, 232 F.3d 1166, 1179 n.9 (9th Cir.

2000).

As Judge Kozinski stated in Corey, a primary purpose of

the Charming Betsy canon is to avoid having a court

“embroil[] the nation in a foreign policy dispute unforeseen

by either the President or Congress.” Id. But when the action

that allegedly violates international law is taken by the

Executive, courts can “presume that the President has

evaluated the foreign policy consequences” of that action

“and determined that it serves the interests of the United

States.” Id.; see also ARC Ecology v. U.S. Dep’t of the Air

Force, 411 F.3d 1092, 1102 (9th Cir. 2005) (same).

Importantly, if courts “construe an authorizing statute

like the AUMF to permit the President to violate international

law,” those courts “would not be placing the United States in

violation of international law. Rather, such a violation would

occur, if at all, only after the Executive Branch, which is both

politically accountable and expert in foreign relations, made

an independent judgment to exercise the authority conferred

by Congress in a way that violated international law.”

Bradley & Goldsmith, Congressional Authorization, 118

HARV. L. REV. at 2098 n.226.

Other judicial decisions have agreed that the Executive’s

interpretation of an ambiguous statute should trump the

Charming Betsy canon and any lurking international-law

norms. For example, the Federal Circuit stated in a

Commerce Department case: “[If] Commerce’s interpretation

of its statutory power falls within the range of permissible

construction . . . that ends our inquiry on this branch of the

56

case. . . . [E]ven if we were convinced that Commerce’s

interpretation conflicts with the [General Agreement on

Tariffs and Trade], which we are not, the GATT is not

controlling.” Suramerica de Aleaciones Laminadas, C.A. v.

United States, 966 F.2d 660, 667 (Fed. Cir. 1992); see also

Timken Co. v. United States, 354 F.3d 1334, 1343-44 (Fed.

Cir. 2004), cert. denied sub nom. Koyo Seiko Co., 543 U.S.

976.

Scholars have likewise maintained that Charming Betsy

should not trump Chevron or Chevron-like deference with

respect to violations of non-self-executing treaties and

customary international law, given that “[v]iolations of those

forms of law, after all, do not substantially implicate domestic

legal continuity; instead, they implicate foreign relations

issues that would seem to fall within the expertise of the

executive branch.” Curtis A. Bradley, Chevron Deference

and Foreign Affairs, 86 VA. L. REV. 649, 689 (2000); see also

Mary Jane Alves, Reflections on the Current State of Play:

Have U.S. Courts Finally Decided To Stop Using

International Agreements and Reports of International Trade

Panels in Adjudicating International Trade Cases?, 17 TUL. J.

INT’L & COMP. L. 299, 315 (2009) (“an agency’s

interpretation of a silent or ambiguous statute” should not be

rejected under Charming Betsy merely because the agency’s

interpretation conflicts with a non-self-executing treaty);

Kristina Daugirdas, International Delegations and

Administrative Law, 66 MD. L. REV. 707, 748 (2007) (in light

of Chevron, courts applying Charming Betsy in cases

involving the Executive should “read ambiguous statutes to

permit (but not to require) agencies to take actions that are

necessary to comply with international legal obligations”);

Arwel Davies, Connecting or Compartmentalizing the WTO

and United States Legal Systems? The Role of the Charming

Betsy Canon, 10 J. INT’L ECON. L. 117, 143 (2007)

57

(Charming Betsy should “not be used to vacate agency

interpretations”).

Put another way, Congress has authority in the first

instance to incorporate international-law norms into a statute.

When Congress has not done so, the Executive still has

authority to construe ambiguities in the statute so as not to

violate international-law norms. Absent action by either

Branch to incorporate or abide by international-law norms,

however, by what authority can courts force those norms on

the political branches?

In sum, when Congress has broadly authorized the

President to take certain actions, and that broad authorization

encompasses actions that might in turn violate international

law, courts have no legitimate basis to invoke international

law as a ground for second-guessing the President’s

interpretation.19

19

To the extent some might find the opinions of foreign or

international tribunals helpful in assessing American law, I note as

a point of comparison that the United Kingdom’s Law Lords have

reached the same conclusion with regard to the British equivalent of

the Charming Betsy canon. In a 1991 decision, the Lords ruled that

Britain’s canon of construction requiring courts to interpret statutes

to conform with international law could not be applied to limit

executive action. See R v. Sec’y of State for the Home Dep’t, Ex

parte Brind, [1991] 1 A.C. 696, 748 (H.L.) (opinion of Lord

Bridge) (“where Parliament has conferred on the executive an

administrative discretion without indicating the precise limits

within which it must be exercised, to presume that it must be

exercised within” limits set by international law “would be a

judicial usurpation of the legislative function”); id. at 761-62

(opinion of Lord Acker) (where a statutory grant of authority to the

Secretary of State “contains within its wording no fetter upon the

extent of the discretion it gives,” the Secretary’s failure to comply

with international law does not “render[] his decision unlawful”; a

58

3

Even if one disagrees with both preceding points about

Charming Betsy, there is another alternative (and still

narrower) reason why the Charming Betsy canon does not

apply to interpretation of the 2001 AUMF. The Charming

Betsy canon may not be invoked against the Executive to limit

the scope of a congressional authorization of war – that is, to

limit a war-authorizing statute to make it conform with non-

self-executing treaties and customary international law.

The Supreme Court has never held that the Charming

Betsy canon applies to a statute that authorizes the President

to use military force against a foreign enemy. For good

reason. Applying Charming Betsy to a statute like the AUMF

would contravene the well-established principle that the

Judiciary should not interfere when the President is executing

national security and foreign relations authority in a manner

consistent with an express congressional authorization (that is,

in Justice Jackson’s Youngstown Category One), at least

unless there is a separate constitutional limitation.

To the extent there is ambiguity in the AUMF, that

ambiguity should be addressed in the first instance by the

President, not by international law or international tribunals.

As Justice Jackson stated in his historic Youngstown opinion,

courts should “indulge the widest latitude of interpretation to

sustain [the President’s] exclusive function to command the

instruments of national force, at least when turned against the

outside world for the security of our society.” Youngstown

contrary conclusion would incorporate international law “into

English domestic law by the back door”).

59

Sheet & Tube Co. v. Sawyer, 343 U.S. 579, 645 (1952)

(Jackson, J., concurring).

That bedrock tenet of judicial restraint has been

articulated by the Supreme Court in numerous cases. As the

Court stated quite plainly in Department of the Navy v. Egan,

for example, “unless Congress specifically has provided

otherwise, courts traditionally have been reluctant to intrude

upon the authority of the Executive in military and national

security affairs.” 484 U.S. 518, 530 (1988); see also Dames

& Moore, 453 U.S. at 678 (“failure of Congress specifically

to delegate authority does not, ‘especially . . . in the areas of

foreign policy and national security,’ imply ‘congressional

disapproval’ of action taken by the Executive”) (quotation

omitted); Agee, 453 U.S. at 291 (“in the areas of foreign

policy and national security . . . congressional silence is not to

be equated with congressional disapproval”); United States v.

Curtiss-Wright Export Corp., 299 U.S. 304, 322 (1936)

(courts should “hesitate long before limiting or embarrassing”

the President’s exercise of foreign relations authority pursuant

to a congressional authorizing statute) (quotation and

emphasis omitted); cf. Chevron, 467 U.S. at 842-45.20

20

Courts sometimes construe the scope of congressional

authorization more narrowly with respect to war-related activities

against U.S. citizens, in part because of the constitutional avoidance

canon. See Ex parte Endo, 323 U.S. 283, 300 (1944) (“In

interpreting a wartime measure we must assume . . . . that the law

makers intended to place no greater restraint on the citizen than was

clearly and unmistakably indicated by the language they used.”).

But see Hamdi, 542 U.S. at 547 (Souter, J., concurring in part,

dissenting in part, and concurring in judgment) (arguing that

plurality had failed to construe AUMF narrowly with regard to an

American citizen detainee); id. at 574 (Scalia, J., dissenting)

(same).

60

That deeply rooted tradition of judicial restraint when the

President is executing national security or foreign affairs

statutes pursuant to a broad congressional authorization stems

from at least three interpretive sources – one based on basic

tenets of statutory interpretation and the tripartite separation

of powers; one based on Article II of the Constitution and the

constitutional avoidance canon; and one based on prudential

considerations.

First, as to statutory interpretation, the Supreme Court

has recognized that Congress, for reasons of practical

necessity and efficiency, often assigns broad authority to the

Executive in the areas of national security and foreign policy.

As the Court has noted, the field of national security and

foreign affairs presents “important, complicated, delicate and

manifold problems.” Curtiss-Wright, 299 U.S. at 319. And

“Congress cannot anticipate and legislate with regard to every

possible action the President may find it necessary to take or

every possible situation in which he might act.” Dames &

Moore, 453 U.S. at 678. Moreover, the President, “not

Congress, has the better opportunity of knowing the

conditions which prevail in foreign countries, and especially

is this true in time of war.” Curtiss-Wright, 299 U.S. at 320.

Therefore, “Congress – in giving the Executive authority over

matters of foreign affairs – must of necessity paint with a

brush broader than that it customarily wields in domestic

areas.” Agee, 453 U.S. at 292 (quotation and emphasis

omitted); see also Curtiss-Wright, 299 U.S. at 320 (foreign

affairs statutes “must often accord to the President a degree of

discretion and freedom from statutory restriction which would

not be admissible were domestic affairs alone involved”); cf.

Egan, 484 U.S. at 529 (“protection of classified information

must be committed to the broad discretion of the agency

responsible” because “an outside non-expert body” is not

competent to make or evaluate such judgments).

61

Courts are thus rightly hesitant to construe foreign affairs

statutes more narrowly than the text indicates, lest they

inadvertently contravene Congress’s prudent and reasonable

decision to afford the President broad discretion in sensitive

and difficult-to-predict national security issues. Put simply,

Congress knows how to limit the Executive’s authority in

national security and foreign policy; there is no reason or

basis for courts to strain to do so absent such congressional

direction.

Second, this traditional deference in interpreting national

security statutes also finds support in the constitutional

avoidance canon. In the domain of foreign relations and

military affairs, the President possesses at least some Article

II authority to act even without congressional authorization,

as explained more fully in Part III below. See, e.g., Egan, 484

U.S. at 529-30; Curtiss-Wright, 299 U.S. at 320. Indeed, in

the text of the AUMF itself, Congress acknowledged that the

President has independent constitutional authority to act

without congressional authorization in defense of the Nation.

See AUMF pmbl., 115 Stat. at 224 (“the President has

authority under the Constitution to take action to deter and

prevent acts of international terrorism against the United

States”); see also War Powers Resolution § 2(c), 50 U.S.C.

§ 1541(c) (President as Commander in Chief has

“constitutional power[]” to introduce U.S. Armed Forces into

hostilities without congressional authorization in response to

an “attack upon the United States, its territories or

possessions, or its armed forces”). That point is perhaps best

exemplified in recent history by a number of significant

military actions taken by President Clinton without

congressional authorization, such as his bombing of suspected

al Qaeda targets in Afghanistan and Sudan in 1998.

62

Courts are therefore properly reluctant to construe broad

national security statutes like the AUMF more restrictively

than their statutory text, lest the courts interfere with the

President’s independent constitutional authority or have to

confront difficult constitutional questions regarding the scope

of the President’s Article II authority to act without

congressional authorization. See Cass R. Sunstein,

Administrative Law Goes to War, 118 HARV. L. REV. 2663,

2670-71 (2005) (“statutory enactments involving core

executive authority” – such as the “authority to protect the

nation when its security is threatened” – “should be construed

hospitably to the President so as to avoid the constitutional

difficulties that a narrow construction would introduce”); see

also Bradley & Goldsmith, Congressional Authorization, 118

HARV. L. REV. at 2098 (questioning whether the Charming

Betsy canon should apply to “a grant of discretionary

enforcement authority to the President” that “overlaps with

the President’s independent constitutional powers”); WILLIAM

N. ESKRIDGE, JR., DYNAMIC STATUTORY INTERPRETATION

325 (1994) (describing “[s]uper-strong rule against

congressional interference with the president’s authority over

foreign affairs and national security”).

Third, prudential considerations likewise suggest that

Charming Betsy is inapposite when courts interpret war-

authorizing statutes. Construing the AUMF to create

judicially enforceable international-law constraints on the

President’s war-related authority would require the Judiciary

to make highly subjective policy judgments that it is not well-

suited to make – and should not make absent congressional

direction. The President’s execution of foreign affairs statutes

often “requires judgments of policy and principle, and the

foreign policy expertise of the executive places it” – not

courts – “in the best position to make those judgments.” Eric

A. Posner & Cass R. Sunstein, Chevronizing Foreign

63

Relations Law, 116 YALE L.J. 1170, 1176 (2007); see id. at

1205-07.

Many international-law norms are vague, contested, or

still evolving. Simply determining the precise content of

those norms at any given time entails a considerable exercise

of subjective judgment. Applying them to particular factual

situations adds another layer of subjectivity. See Sosa v.

Alvarez-Machain, 542 U.S. 692, 726 (2004) (“a judge

deciding in reliance on an international norm will find a

substantial element of discretionary judgment in the

decision”); JACK L. GOLDSMITH & ERIC A. POSNER, THE

LIMITS OF INTERNATIONAL LAW 23-24 (2005) (discussing

difficulties in ascertaining content of customary international

law). And deciding how those international-law norms

should apply to a war that differs in fundamental ways from

traditional models of armed conflict presents especially

thorny questions of policy and prudence. Moreover, judicial

assessment of contested international-law norms can take

years, but the President often needs to make military decisions

immediately or at least quickly – a reality that calls for

judicial caution before restraining the President’s exercise of

war powers.

Thus, it is hard to conceive of a task less appropriate for

U.S. judges – or less consistent with our constitutional

structure – than judicial invocation, without a constitutional or

congressional mandate, of uncertain and changing

international-law norms to restrain the President and the U.S.

military in waging a congressionally authorized war abroad.

It is the President’s duty and responsibility to win the war, in

a manner consistent with the Constitution and with

constitutionally permissible limits imposed by Congress.

Courts should not interfere with that effort unless the

64

Constitution, a federal statute, or a self-executing treaty so

requires.21

21

A fine illustration of the difficulty of applying international-

law norms is the recent back-and-forth over the proper legal

framework for targeted killing of alleged terrorists by the United

States using unmanned aerial vehicles, or “drones,” in Pakistan and

elsewhere.

In March 2010, the Legal Adviser to the U.S. State

Department asserted that U.S. drone operations “comply with all

applicable law, including the laws of war.” Harold Hongju Koh,

Legal Adviser, U.S. Dep’t of State, The Obama Administration and

International Law: Address at the Annual Meeting of the American

Society of International Law (Mar. 25, 2010). The Legal Adviser

took the position that “as a matter of international law, the United

States is in an armed conflict with al-Qaeda, as well as the Taliban

and associated forces” and that “individuals who are part of such an

armed group are belligerents and, therefore, lawful targets under

international law.” Id.

Some of those conclusions were subsequently challenged,

however, by the United Nations Special Rapporteur on

Extrajudicial, Summary or Arbitrary Executions, Professor Philip

Alston. See U.N. Human Rights Council, Report of the Special

Rapporteur on Extrajudicial, Summary or Arbitrary Executions,

Addendum: Study on Targeted Killings, U.N. Doc.

A/HRC/14/24/Add.6 (May 28, 2010) (prepared by Philip Alston).

Special Rapporteur Alston stated that it was “problematic” for the

United States to claim that it is in an armed conflict with al Qaeda,

the Taliban, and associated forces “outside the context of the armed

conflicts in Afghanistan or Iraq,” and that if the United States is not

in an armed conflict with al Qaeda, such targeted killings “cannot

be legal” under international law. Id. ¶¶ 33, 53. Special

Rapporteur Alston also maintained that even assuming the United

States is in an armed conflict with al Qaeda, international law still

would not permit the United States to target individuals based on

mere “membership” in al Qaeda, but would instead require the

United States to demonstrate that those individuals’ conduct rose to

the level of “direct participation in hostilities.” See id. ¶ 58, 62-67.

65

Consider some of the radical implications of the position

advanced by Al-Bihani and amici. The 15 judges on the

International Court of Justice include judges from China,

Russia, Jordan, Somalia, France, Brazil, and Sierra Leone,

among other nations. Suppose, for example, that the ICJ

issues an important ruling on a matter of international law

related to the U.S. war against al Qaeda. One can have the

greatest respect (as I do) for the judges on the ICJ and at the

same time think it odd for a U.S. court to give more weight to

the views of Chinese and Russian jurists, for example, than to

the interpretation of the U.S. President when the court is

interpreting a domestic U.S. war-authorizing statute that does

not itself reference international law. Yet that is the necessary

and highly irregular result of the approach advocated by Al-

Bihani and his amici.

In light of those statutory, constitutional, and prudential

considerations, we would upend Supreme Court precedent

and basic elements of our constitutional architecture were we

to apply the Charming Betsy canon to war-authorization

statutes such as the 2001 AUMF. Courts should not rely on

Charming Betsy to transform affirmative congressional

authorization of a war into a legislative mandate for courts to

restrain the President’s conduct of that war based on

sometimes vague, contested, or still-evolving international-

law principles.

This rather stark difference of opinion between the U.S. State

Department and the U.N. Special Rapporteur simply underscores

the murkiness and uncertainty surrounding the application of

international-law norms to the war in which the United States is

presently engaged. It suggests that judges should not wade into

debates of this kind and hamper the President’s direction of a war

without a constitutional or congressional mandate to do so.

66

* * *

To sum up on Charming Betsy: The canon exists to the

extent it supports applying the presumption against

extraterritorial application of federal statutes. Beyond that,

after Erie and particularly after Sosa and Medellín, it is not

appropriate for courts to use the Charming Betsy canon to

alter interpretation of federal statutes to conform them to

norms found in non-self-executing treaties and customary

international law, which Congress has not chosen to

incorporate into domestic U.S. law. In the alternative, even if

one disagrees with that broader proposition and concludes that

use of the Charming Betsy canon is appropriate in some such

cases, it should not be invoked against the Executive Branch,

which has the authority to weigh international-law

considerations when interpreting the scope of ambiguous

statutes. And even if one also disagrees with that, it is not

appropriate for courts to narrow a congressional authorization

of war based on international-law norms that are not part of

domestic U.S. law.

E

Al-Bihani and amici cite Hamdi v. Rumsfeld to support

their argument that the President’s authority under the AUMF

is limited by international law. They assert that Hamdi in

effect already applied Charming Betsy to the AUMF. That

contention is erroneous.

The detainee in Hamdi was a U.S. citizen who argued

that his detention was forbidden by the Non-Detention Act.

That Act prohibits detention of U.S. citizens unless authorized

by statute. See 18 U.S.C. § 4001(a). The relevant questions

for the Hamdi Court, therefore, were (i) whether the AUMF

authorized detention of enemy combatants in the war against

67

al Qaeda and the Taliban, (ii) whether that authority

encompassed detention of U.S. citizen enemy combatants, and

(iii) whether such detention could last for the duration of the

war, even though the war might last for decades.

Justice O’Connor’s plurality opinion first answered the

threshold question whether the AUMF authorized detention.

It pointed out that detention is a “fundamental incident of

waging war” and, for that reason, is “clearly and

unmistakably authorized” by the AUMF’s grant of authority

to employ “necessary and appropriate” military force. 542

U.S. at 519 (plurality opinion of O’Connor, J.). That point

was, of course, fairly obvious: At its core, war consists of

killing, capturing, and detaining the enemy. In any event, in

reaching that conclusion, the plurality “looked to prior

Executive Branch practice during wartime to inform its

interpretation” of the AUMF. Bradley & Goldsmith,

Congressional Authorization, 118 HARV. L. REV. at 2085.

The plurality also pointed to some international law-of-war

sources as evidence that the “universal agreement and

practice” among civilized nations supported the conclusion

that detention was a fundamental incident of warfare. Hamdi,

542 U.S. at 518 (plurality opinion of O’Connor, J.) (quoting

Ex parte Quirin, 317 U.S. 1, 30 (1942)).

Next, the Court found that the AUMF’s authorization of

detention encompassed detention of enemy combatants who

were U.S. citizens. The Court noted that the United States

had detained U.S. citizens as enemy combatants in the past,

including during World War II. The Court also recognized

that “such a citizen, if released, would pose the same threat of

returning to the front during the ongoing conflict” as a non-

citizen detainee. Id. at 519.

68

Finally, the Court addressed Hamdi’s concern about

“indefinite or perpetual detention” in light of the expected

duration of the war against al Qaeda and the Taliban. Id. at

521. Hamdi in essence argued that there must be some

implied limit to the duration of the President’s authority under

the AUMF, lest Hamdi spend the rest of his life in detention.

In rejecting that contention, the plurality opinion initially

noted that indefinite detention simply “for the purpose of

interrogation” was not authorized by the AUMF; in other

words, the Court stated th

This text is long and has been trimmed here. Open the source document for the complete record.