Amicus Curiae Brief — Donald J. Trump, President of the United States, et al., Petitioners v. Barbara, et al.

No. 25-365

In the

Supreme Court of the United States

DONALD J. TRUMP, PRESIDENT

OF THE UNITED STATES, et al.,

Petitioners,

v.

BARBARA, et al.,

Respondents.

On Writ of Certiorari Before Judgment to the

United States Court of A ppeals for the First Circuit

AMERICA FIRST POLICY INSTITUTE

AS AMICUS CURIAE

IN SUPPORT OF PETITIONERS

Brian Kelsey

Counsel of Record

Gina D’A ndrea

A ndrew Zimmitti

Leigh A nn O’Neill

T yler Cochran

A merica First Policy Institute

1455 Pennsylvania Avenue, NW,

Suite 225

Washington, DC 20004

(703) 637-3690

bkelsey@americafirstpolicy.com

January 27, 2026

131922

Counsel for Amicus Curiae

A

(800) 274-3321 • (800) 359-6859

i

TABLE OF CONTENTS

Page

TABLE OF CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . i

TABLE OF CITED AUTHORITIES . . . . . . . . . . . . . . . ii

INTEREST OF THE AMICUS CURIAE . . . . . . . . . . 1

SUMMARY OF THE ARGUMENT . . . . . . . . . . . . . . . 2

ARGUMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

I.

The Fourteenth Amendment requires both

residence and allegiance as conditions to

citizenship . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

II. Allegiance is more important to the common

law doctrine of birthright citizenship than

place or parentage . . . . . . . . . . . . . . . . . . . . . . . . . 6

A. The English common law doctrine of

natural-born subjectship was rooted in

a robust understanding of allegiance . . . . . .6

B. The children of illegal aliens do not

satisfy the allegiance condition of

constitutional citizenship . . . . . . . . . . . . . . . . 8

CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

ii

TABLE OF CITED AUTHORITIES

Cases

Page

Baynard v. Singleton,

1 N.C. 5 (1787) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Benny v. O’Brien,

58 N.J.L. 36 (N.J. 1895) . . . . . . . . . . . . . . . . . . . . . . . . 4

Calvin’s Case,

77 Eng. Rep. 377 (K.B. 1608) . . . . . . . . . . . . . . . . 6, 7, 8

Elk v. Wilkins,

112 U.S. 94 (1884) . . . . . . . . . . . . . . . . . . . . . . . . . . . 3, 8

Hamilton v. Eaton,

1 N.C. 641 (Cir. Ct. D.N.C. 1792) . . . . . . . . . . . . . . . . . 9

Hardy v. De Leon,

5 Tex. 211 (Tex. 1849) . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Inglis v. Trustees of Sailor’s Snug Harbor,

28 U.S. 99 (1830) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

INS v. Lopez-Mendoza,

468 U.S. 1032 (1984) . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Jackson v. White,

20 Johns. 313 (N.Y. Sup. Ct. 1822) . . . . . . . . . . . . . . . . 9

Ludlam v. Ludlam,

31 Barb. 486 (N.Y. 1860) . . . . . . . . . . . . . . . . . . . . . . . . 4

iii

Cited Authorities

Page

M’Ilvaine v. Coxe’s Lesee,

6 U.S. 280 (1805) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Marbury v. Madison,

5 U.S. 137 (1803) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

N.Y. State Rifle & Pistol Ass’n, Inc. v. Bruen,

597 U.S. 1 (2022) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Oregon v. Mitchell,

400 U.S. 112 (1970) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Respublica v. Chapman,

1 U.S. 53 (Pa. 1781) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

United States v. Wong Kim Ark,

169 U.S. 649 (1898) . . . . . . . . . . . . . . . . . . . . 3, 6, 7, 8, 9

Constitutional Provisions

U.S. Const. amend. XIV, § 1 . . . . . . . . . . . . . . . . . . . . . . . 2

Statutes and Other Authorities

Act of July 27, 1868, ch. 249, § 1, 15 Stat. 223 . . . . . . . . . 9

Act of English Parliament, 23 Eliz. 1 (1580) . . . . . . . . . . 7

Act of English Parliament, 42 Edw. 3, c. 10 (1368) . . . . . 7

Sup. Ct. R. 37.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

iv

Cited Authorities

Page

Kerry Abrams, The Hidden Dimension of

Nineteenth- Centur y Immigration Law,

62 Vand. L. Rev. 1353 (2019) . . . . . . . . . . . . . . . . . . . . 5

1 William Blackstone, Commentaries on the Laws

of England (1765) . . . . . . . . . . . . . . . . . . . . . . . . . . . 7, 8

Cong. Globe, 39th Cong.,

1st Sess. 1117, 2893 (1866) . . . . . . . . . . . . . . . . . . . . . . 5

Adam B. Cox, The Invention of Immigration

Exceptionalism, 134 Yale L.J. 329 (2024) . . . . . . . . . 5

The Declaration of Independence

para. 2, 32 (U.S. 1776) . . . . . . . . . . . . . . . . . . . . . . . . . . 9

James H. Ketter, The Development of American

Citizenship, 1608-1870 (1978) . . . . . . . . . . . . . . . . . . . . 7

Bradford Perkins, Prologue to War: England and

the United States 1805-1812 (1961) . . . . . . . . . . . . . . . 9

Gage Raley, Could the Supreme Court Defy the

“Legal Consensus” and Uphold a Trump-like

Executive Order on Birthright Citizenship?

17 Charleston L. Rev. 95 (2022) . . . . . . . . . . . . . . . 9, 10

Joseph Story, Commentaries on the Conflict of

Laws, Foreign and Domestic, in Regard to

Contracts, Rights, and Remedies, and Especially

in Regard to Marriages, Divorces, Wills,

Successions, and Judgments (1834) . . . . . . . . . . . . 4, 8

v

Cited Authorities

Page

A my S wea rer, Subject t o th e [Co mpl et e]

Ju r i s d i c t i o n T h e r e of : Sa l v a g i n g t h e

Original Meaning of the Citizenship Clause,

24 Tex. Rev. L. & Pol. 135 (2020) . . . . . . . . . . . . . . . . 5

1

INTEREST OF THE AMICUS CURIAE1

The America First Policy Institute (AFPI) is a 501(c)

(3) non-profit, non-partisan research institute. AFPI exists

to advance policies that put the American people first. Our

guiding principles are liberty, free enterprise, national

greatness, American military superiority, foreign-policy

engagement in the American interest, and the primacy of

American workers, families, and communities in all we do.

AFPI believes both the Executive and Legislative

branches have broad constitutional authority over matters

of immigration and foreign relations and have extensive

powers related to national defense and sovereignty.

Accordingly, AFPI believes that each branch has the

power and the duty to end birthright citizenship for

children of illegal aliens, alien tourists, and aliens in

the U.S. legally but temporarily. Along with being

constitutionally valid, revoking birthright citizenship

for these categories of aliens is also sound policy that

protects the value of citizenship in the United States.

An America-first approach to immigration policy not

only guarantees the security of the border and defends

American citizens against the malignant influence of drug

cartels, human traffickers, and terrorist organizations,

but it also protects the citizenry against the dilution of

their rights and powers.

1. No counsel for a party authored this brief, in whole or in

part, and no person or entity other than amicus curiae made a

monetary contribution to the preparation or submission of the

brief. Sup. Ct. R. 37.6.

2

SUMMARY OF THE ARGUMENT

The Citizenship Clause of the Fourteenth Amendment

builds upon the history and tradition of birthright

citizenship in Anglo-American law, making it clear that

for one to be recognized as a citizen he must satisfy two

conditions: residence and allegiance. This two-pronged

approach to citizenship has deep roots in the common law

tradition. Accordingly, while the children of temporary

residents and the children of illegal aliens are born within

the dominions of the United States in satisfaction of the

residence condition, they do not possess the requisite

allegiance necessary to be recognized as citizens under

the Fourteenth Amendment.

ARGUMENT

I.

The Fourteenth Amendment requires both residence

and allegiance as conditions to citizenship.

The Fourteenth Amendment states, “All persons born

or naturalized in the United States, and subject to the

jurisdiction thereof, are citizens of the United States.”

U.S. Const. amend. XIV, § 1. The plain text makes clear

that birth within the dominions of the United States is an

essential element of constitutional citizenship. However,

the plain text also makes clear that the phrase “subject

to the jurisdiction thereof” must be read as necessitating

a second condition. This Court has long recognized

the surplusage canon of constitutional interpretation,

requiring that no clause in the Constitution be read as to

render it meaningless. Marbury v. Madison, 5 U.S. 137,

174 (1803). Therefore, “subject to the jurisdiction thereof”

must serve a greater function within the Fourteenth

3

Amendment than merely reaffirming the preceding

clause outlining the residence condition to constitutional

citizenship. Ultimately, this additional clause is most

reasonably read as codifying the condition of allegiance

that undergirded the common law doctrine of birthright

citizenship.

This Court has long recognized the importance of

allegiance to understanding the Fourteenth Amendment’s

notion of citizenship. In Elk v. Wilkins, the Court held,

“The evident meaning of these last words is, not merely

subject in some respect or degree to the jurisdiction of

the United States, but completely subject to their political

jurisdiction, owing them direct and immediate allegiance.”

112 U.S. 94, 102 (1884). Additionally, in United States

v. Wong Kim Ark, the Court again explicitly equated

allegiance with jurisdiction. 169 U.S. 649, 655 (1898).

Understanding “subject to the jurisdiction thereof” as

referring to more than mere regulatory jurisdiction is also

the best way to make sense of the universally recognized

exceptions to birthright citizenship present at common law

and upheld by this Court — namely children of foreign

ambassadors, children of alien enemies, and children

belonging to the American Indian tribes. See id. at 68081, 693. The primary justification for exclusion of these

groups is that they lack the requisite allegiance that would

mark them as citizens, clearly demonstrating that birth

on U.S. soil is insufficient on its own to confer citizenship.

Undoubtedly, the children of temporary residents and

children of illegal aliens are not universally recognized

exceptions at common law. However, that does not mean

that they are prima facie precluded from the implied

4

exclusions of the Fourteenth Amendment. This Court has

held that “analogical inquiry” grounded in our “Nation’s

historical traditions[s]” help to illuminate the meaning and

application of the text of the Constitution. N.Y. State Rifle

& Pistol Ass’n, Inc. v. Bruen, 597 U.S. 1, 17, 29 (2022).

Therefore, the question before this Court is not whether

the Fourteenth Amendment contemplates exceptions

to the general rule of birthright citizenship — it clearly

does — but whether the subjects of President Trump’s

executive order — children of temporary residents and

children of illegal aliens — are more analogous to the

already recognized exceptions or to those subject to the

general rule.

Historically, American law has not limited itself to

the primary, universally recognized exceptions to the

common law rule of birthright citizenship. Justice Story

identified as a “reasonable qualification” to the general

rule that persons born to parents who are temporary

residents are not citizens of the country in which their

parents temporarily reside. Joseph Story, Commentaries

on the Conflict of Laws, Foreign and Domestic, in Regard

to Contracts, Rights, and Remedies, and Especially in

Regard to Marriages, Divorces, Wills, Successions, and

Judgments 48 (1834). While not universal, this exception

experienced widespread support among the various states

well into the 19th century, including after passage of the

Fourteenth Amendment. See Benny v. O’Brien, 58 N.J.L.

36, 39 (N.J. 1895); Hardy v. De Leon, 5 Tex. 211, 237 (Tex.

1849); Ludlam v. Ludlam, 31 Barb. 486, 503 (N.Y. 1860).

An exception for the children of temporary residents was

also recognized by numerous members of Congress who

participated in the debates surrounding the Citizenship

Clause and similar relevant sections of the Civil Rights

5

Act of 1866, including Representative James Wilson and

Senator Benjamin Wade. Cong. Globe, 39th Cong., 1st

Sess. 1117, 2893 (1866). Therefore, it cannot be assumed

that the Fourteenth Amendment’s silence on this disputed

exception precludes it any more than silence precludes the

universally recognized exceptions.

The historical record has little to say regarding an

exception for the children of illegal aliens. Yet, this is

not because such children were widely considered to fall

under the general rule of birthright citizenship. Rather, it

is because illegal immigration as we know it did not exist

at the time of the framing of the Fourteenth Amendment.

Prior to the late 19th century, regulating immigration was

primarily the province of the states and not the federal

government. See generally Kerry Abrams, The Hidden

Dimension of Nineteenth-Century Immigration Law, 62

Vand. L. Rev. 1353 (2019). The first federal law broadly

restricting immigration did not pass until 1882, and

the border was not regularly policed until the Border

Patrol was created in 1924. Amy Swearer, Subject to the

[Complete] Jurisdiction Thereof: Salvaging the Original

Meaning of the Citizenship Clause, 24 Tex. Rev. L. &

Pol. 135, 178 (2020); Adam B. Cox, The Invention of

Immigration Exceptionalism, 134 Yale L.J. 329, 378

(2024). Therefore, this Court should not interpret the plain

text of the Citizenship Clause as presumptively conferring

citizenship to a category of people not contemplated by the

drafters of the Fourteenth Amendment. To do so would

be an exercise of a “general authority to establish norms

for the rest of society” that the judiciary does not possess.

Oregon v. Mitchell, 400 U.S. 112, 203 (1970) (Harlan, J.,

concurring). Instead, the Court should turn to the history

and tradition of birthright citizenship in Anglo-American

6

law to determine whether an exception for the children

of illegal aliens is analogous to those already universally

recognized. Ultimately, an examination of this history

and tradition reveals that children of illegal aliens are not

considered citizens under the Fourteenth Amendment.

II. Allegiance is more important to the common law

doctrine of birthright citizenship than place or

parentage.

A.

The English common law doctrine of naturalborn subjectship was rooted in a robust

understanding of allegiance.

While history and tradition always play a significant

role in constitutional interpretation, they are especially

crucial to understanding constitutional citizenship.

Citizenship under the English common law system has

long been recognized as an important historical resource

to understanding and applying the Citizenship Clause.

Nowhere is this more evident than in this Court’s reliance

on Calvin’s Case, 77 Eng. Rep. 377 (K.B. 1608), in Wong

Kim Ark, where the Court stated that the Citizenship

Clause “must be interpreted in the light of the common

law.” See 169 U.S. at 655-56, 690.

The English common law system long affirmed a

qualified form of jus soli2 citizenship whereby persons

2. Literally, “right of the soil.” Jus soli is the law that anyone

born within the dominions of a given nation is presumptively a

citizen of that nation. This is a distinct concept from jus sanguinis,

or “right of blood,” which grounds citizenship in the nationality

of one’s parents.

7

born within the royal dominions were generally subjects

of the king, owing him their obeisance in perpetuity. See

generally James H. Ketter, The Development of American

Citizenship, 1608-1870 13-46 (1978); 42 Edw. 3, c. 10

(1368). See also 23 Eliz. 1 (1580). However, the common

law did not promote a pure jus soli concept of citizenship.

Rather, contrary to popular belief, under the common law

system, what is more important than place or parentage

in determining citizenship status is one’s allegiance.

As recognized by this Court in Wong Kim Ark,

allegiance is nowhere more prominent than in the oftcited and oft-misunderstood Calvin’s Case. 169 U.S.

at 655 (“the fundamental principle of the common law

. . . was . . . allegiance”). In Calvin’s Case, Judge Coke

defined allegiance as the “true and faithful obedience of

the subject due to his sovereign.” 77 Eng. Rep. at 382.

To Judge Coke, he who receives protection from the

sovereign by “birthright” owes “ligeance and obedience”

to the sovereign just as the child owes “ligeance and

obedience” to his parents. Id. at 383; see also Ketter,

supra, 18. 3 Therefore, under the English common law

system, citizenship is irrevocably tied to the bond between

sovereign and subject derived from the allegiance

possessed by one born within the sovereign’s realm and,

by extension, under the sovereign’s protection. However,

the common law doctrine of birthright citizenship was

not unqualified.

3. A similar emphasis on allegiance can be found in William

Blackstone’s influential Commentaries, written 150 years after

Calvin’s Case, thereby demonstrating the staying power of the

concept of tying citizenship to allegiance. See 1 William Blackstone,

Commentaries on the Laws of England 358, 369-70 (1765).

8

Calvin’s Case states that the general rule of naturalborn subjectship applies only if a person’s parents were

“under the actual obedience of the King.” 77 Eng. Rep.

at 399. No one can “be a subject to the King . . . unless

at the time of his birth he was under the ligeance and

obedience of the King.” Id. Based on this reasoning, two

primary exceptions to the common-law rule of naturalborn subjectship existed for children of ambassadors

and invaders because their parents held no actual

allegiance to the king. Id. at 383; Blackstone, supra, at

373. These children are excluded from the general rule

because, at common law, the children of non-citizens

born within the dominions of the sovereign were divided

into two camps: alien enemies and alien friends. Calvin’s

Case, 77 Eng. Rep. at 397; Blackstone, supra, at 37273. Alien friends owed allegiance to the sovereign and

had certain rights and privileges while alien enemies,

who bore no such allegiance, did not possess those same

rights and privileges. Blackstone, supra, at 372-73. This

categorization of aliens has long been recognized in

American law. See Story, supra, 48; see also Elk, 112 U.S.

at 102; Wong Kim Ark, 169 U.S. at 682. Therefore, in order

to determine whether or not the children of illegal aliens

are citizens under the Fourteenth Amendment, the Court

must determine whether their parents are more analogous

to alien friends or alien enemies.

B. The children of illegal aliens do not satisfy

the allegiance condition of constitutional

citizenship.

Under the common law doctrine of birthright

citizenship, allegiance and obedience — not soil — is what

marks persons as citizens. This emphasis on allegiance is

9

not a vestige of a bygone era but persisted as an important

element in determining citizenship in the American context

even after the passage of the Fourteenth Amendment.4

Ultimately, the children of illegal aliens do not inherit

the requisite allegiance and obedience from their parents

because their parents are aliens in enmity with the United

States. Therefore, these children should be considered

an exception to the general rule of birthright citizenship.

Illegal immigrants are necessarily in enmity with the

country they enter because they have broken the law by

crossing its borders. By definition, illegal immigration

betrays a lack of allegiance to the laws of the sovereign.

Gage Raley, Could the Supreme Court Defy the “Legal

Consensus” and Uphold a Trump-like Executive Order

4. In fact, allegiance may be even more important in the

American context, given America’s robust, historical emphasis

on actual allegiance in determining questions of citizenship, as

demonstrated by the Declaration of Independence, the “right of

election” in the aftermath of the colonies’ separation from Great

Britain, the impressment controversy that led to the War of 1812,

and the 1868 Expatriation Act. The Declaration of Independence

para. 2, 32 (U.S. 1776); Respublica v. Chapman, 1 U.S. 53, 58 (Pa.

1781); Baynard v. Singleton, 1 N.C. 5 (1787); Hamilton v. Eaton,

1 N.C. 641 (Cir. Ct. D.N.C. 1792); Jackson v. White, 20 Johns. 313

(N.Y. Sup. Ct. 1822); M’Ilvaine v. Coxe’s Lesee, 6 U.S. 280 (1805);

Inglis v. Trustees of Sailor’s Snug Harbor, 28 U.S. 99 (1830);

Bradford Perkins, Prologue to War: England and the United

States 1805-1812 89-90 (1961); Act of July 27, 1868, ch. 249, § 1, 15

Stat. 223. Additionally, this Court in Wong Kim Ark recognized

that allegiance is not a one-way street but contains an element of

mutual consent. See 169 U.S. at 694 (persons “are entitled to the

protection of and owe allegiance to the United States, so long as

they are permitted by the United States to reside here”) (emphasis

added).

10

on Birthright Citizenship? 17 Charleston L. Rev. 95, 11213 (2022). Essentially, illegal immigration demonstrates

a refusal to recognize the sovereign’s right to rule. Id. at

113. Moreover, unlike other crimes, it is an ongoing act of

defiance, or an “ongoing crime.” INS v. Lopez-Mendoza,

468 U.S. 1032, 1047 n. 3 (1984). Because their parents

have demonstrated a lack of allegiance to the governing

authorities, children of illegal aliens cannot inherit the

allegiance that defines the common law rule of naturalborn subjectship. Parents cannot pass onto their children

that which they do not themselves possess.

Additionally, illegal aliens do not possess the same

protections afforded to citizens or legal residents. Since

they have no right to dwell in the country in which they

are illegally present, illegal aliens face the constant threat

of removal from the sovereign’s dominion. This threat

further ensures that children of illegal aliens will not

possess the allegiance required by the common law rule.

Instead of seeing the sovereign as a protector, they may

see him as a persecutor, thereby incurring “grudge[s]

of resentment as opposed to debts of gratitude.” Raley,

17 Charleston L. Rev. at 114. Accordingly, were illegal

immigration as it exists in the modern era to have been

present under the common law, illegal alien children

likely would have been denied citizenship as children of

aliens in enmity with the sovereign. Therefore, it would

be in keeping with both the plain text of the Citizenship

Clause and the history and tradition of citizenship in

Anglo-American law to exclude the children of illegal

aliens from the privileges of citizenship.

11

CONCLUSION

For these reasons stated herein, amicus curiae

respectfully requests that this Court vacate the lower court’s

injunction of the executive order and allow the political

branches to make determinations concerning citizenship

and naturalization pursuant to their constitutional duties.

Respectfully submitted,

Brian Kelsey

Counsel of Record

Gina D’A ndrea

A ndrew Zimmitti

Leigh A nn O’Neill

T yler Cochran

A merica First Policy

Institute

1455 Pennsylvania Avenue, NW,

Suite 225

Washington, DC 20004

(703) 637-3690

bkelsey@americafirstpolicy.com

January 27, 2026

Counsel for Amicus Curiae