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 Appeals for the First Circuit

BRIEF OF AMICUS CURIAE

PROFESSOR AKHIL REED AMAR

IN SUPPORT OF RESPONDENTS

Vikram David Amar

Counsel of Record

UNIVERSITY OF CALIFORNIA, DAVIS SCHOOL OF LAW

400 Mrak Hall Drive

Davis, CA 95616

(925) 858-8855

vdamar@ucdavis.edu

February 23, 2026

SUPREME COURT PRESS

Counsel for Amicus Curiae

♦

(888) 958-5705

♦

BOSTON, MASSACHUSETTS

i

TABLE OF CONTENTS

Page

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

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

SUMMARY OF ARGUMENT .................................... 1

ARGUMENT ............................................................... 4

I.

What Is the Plain Meaning of the Citizenship Clause? ..................................................... 4

II. What Is the Big Idea? ...................................... 9

III. What Does the Phrase “Subject to the

Jurisdiction” Mean and What Does It Not

Mean? ............................................................. 16

IV. What Do This Court’s Relevant

Fourteenth Amendment Precedents Say?..... 20

V. What Do Leading Fourteenth Amendment

Scholars Say? ................................................. 24

VI. What Should the Court Make of the

Solicitor General’s Petitioner Brief? .............. 24

VII. How Does President Trump’s Executive

Order Fare Under Marbury and

Youngstown? ................................................... 28

VIII. What Should the Court Make of the

Various Lines Drawn in E.O. 14160? ............ 29

IX. Why Should the Court Decide the Big

Constitutional Question of Birthright

Citizenship When There Are Off-Ramps

Available? ....................................................... 30

X. Why Is This the Most Important Case of

the Century (So Far)? .................................... 31

CONCLUSION.......................................................... 33

ii

TABLE OF AUTHORITIES

CASES

TABLE OF AUTHORITIES

Page

Calvin’s Case,

77 Eng. Rep. 377 (K.B. 1608) ...................... 13, 14

Caperton v. A.T. Massey Coal Co.,

556 U.S. 868 (2009) ............................................. 6

Dobbs v. Jackson Women’s Health Org.,

597 U.S. 215 (2022) ..................................... 22, 28

Dred Scott v. Sandford,

60 U.S. (19 How.) 393 (1857) .......... 11, 12, 13, 32

Hirabayashi v. United States,

320 U.S. 81 (1943) ............................................. 21

INS v. Errico,

385 U.S. 214 (1966) ........................................... 21

INS v. Rios-Pineda,

471 U.S. 444 (1985) ........................................... 21

Lynch v. Clarke,

1 Sand. Ch. 583 (N.Y. Ch. 1844) ....................... 14

Marbury v. Madison,

5 U.S. (1 Cranch) 137 (1803) ................. 28, 31, 32

Morrison v. California,

291 U.S. 82 (1934) ............................................. 21

Murphy v. Smith,

583 U.S. 220 (2018) ........................................... 26

Planned Parenthood of Se. Pa. v. Casey,

505 U.S. 833 (1992) ............................................. 6

Plessy v. Ferguson,

163 U.S. 537 (1896) ..................................... 22, 23

iii

TABLE OF AUTHORITIES (Cont.)

Page

Plyler v. Doe,

457 U.S. 202 (1982) ........................................... 21

Trump v. CASA, Inc.,

606 U.S. 831 (2025) ........................................... 21

United States ex rel. Hintopoulos

v. Shaughnessy, 353 U.S. 72 (1957) .................. 21

United States v. Wong Kim Ark,

169 U.S. 649 (1898) ................ 3, 16, 20-24, 27, 28

Weedin v. Chin Bow,

274 U.S. 657 (1927) ........................................... 21

Youngstown Sheet & Tube Co. v. Sawyer,

343 U.S. 579 (1952) ........................... 3, 27, 30, 32

CONSTITUTIONAL PROVISIONS

U.S. Const. amend. XIV .. 6, 8, 11, 13, 22-24, 27-29, 31

STATUTES

16 Stat. 544 ................................................................. 9

8 U.S.C. § 1101(b) ..................................................... 29

8 U.S.C. § 1401(a) ............................................... 28, 29

8 U.S.C. § 1403(a) ..................................................... 29

8 U.S.C. § 1403(b) ..................................................... 29

8 U.S.C. § 1409(a)(1)-(4) ........................................... 29

iv

TABLE OF AUTHORITIES (Cont.)

Page

Civil Rights Act of 1866, 14 Stat. 27 ........................ 13

Indian Citizenship Act of 1924, 43 Stat. 253 ............. 9

Naturalization Act of 1855, § 1, 10 Stat. 604............. 6

Naturalization Act of 1870, 16 Stat. 254 ................. 23

EXECUTIVE ORDERS

E.O. 14160,

Protecting the Meaning and Value of

American Citizenship .......... 16, 18, 20, 29, 30, 31

OTHER AUTHORITIES

AKHIL REED AMAR,

AMERICA’S CONSTITUTION: A BIOGRAPHY

(2005) ................................................................... 5

Akhil Reed Amar,

America’s Equal Citizenship Clause,

NAT’L CONST. CTR.,

https://constitutioncenter.org/theconstitution/amendments/amendmentxiv/clauses/700 ................................................... 10

AKHIL REED AMAR,

AMERICA’S UNWRITTEN CONSTITUTION:

THE PRECEDENTS AND PRINCIPLES WE LIVE

BY (2012) ............................................................ 22

AKHIL REED AMAR,

BORN EQUAL: REMAKING AMERICA’S

CONSTITUTION, 1840-1920 (2025)........ 7, 8, 10, 22

CONG. GLOBE,

39th Cong., 1st Sess. (1866) 16, 17, 18, 20, 25, 26

v

TABLE OF AUTHORITIES (Cont.)

Page

DAILY BEE (Cal.) (June 30, 1868)................................ 5

Edward Bates, Att’y Gen.,

Op. of Att’y Gen on Citizenship

(Nov. 29, 1862) ................................................... 12

FRANKFORT COMMONWEALTH (July 3, 1866) .............. 5

Gerard N. Magliocca,

Without Domicile or Allegiance: Gypsies

and Birthright Citizenship, 49 HARV. J.L.

& PUB. POL’Y 539 (2026) .................................... 20

GOLD HILL DAILY NEWS (Nev.) (Aug. 17, 1866) ......... 5

Granville Moody, General,

Speech, PITTSBURGH COM. (Sep. 26, 1866) .......... 5

H. W. HALLECK,

INTERNATIONAL LAW 209 (1861) ........................ 17

Hannibal Hamlin,

Speech, N.Y. DAILY HERALD (Oct. 6, 1866)........... 4

Hannibal Hamlin,

Speech, N.Y. DAILY HERALD (Oct. 16, 1866) ........ 5

James M. Ashley,

Speech, JACKSON DAILY CITIZEN (Mich.)

(Nov. 3, 1866) ....................................................... 5

James P. McClure, et al., eds.,

Circumventing the Dred Scott Decision:

Edward Bates, Salmon P. Chase, and the

Citizenship of African Americans, 43 CIV.

WAR HIST. 279 (1997) ........................................ 13

vi

TABLE OF AUTHORITIES (Cont.)

Page

Joseph C. Lewis,

July 2 Public Letter of Speaker Colfax,

N.Y. TIMES, July 16, 1866 ................................... 5

Kurt T. Lash,

Prima Facie Citizenship: Birth, Allegiance

and the Fourteenth Amendment’s

Citizenship Clause, 101 NOTRE DAME L.

REV. (forthcoming 2026) .................................... 15

Memorandum from Edward Bates, Att’y Gen.,

to William Seward, Sec’y of State (Sep. 1,

1862) .................................................................. 12

Richard J. Oglesby, Illinois Governor,

Speech, CARTHAGE GAZETTE (Ill.)

(May 3, 1866) ....................................................... 5

Samarth Desai,

Birthright Citizenship: A Test Case,

VOLOKH CONSPIRACY (Feb. 18, 2025),

http://bit.ly/4qpFSGK .......................................... 7

Schuyler Colfax,

Speech, CINCINNATI COM. (Aug. 7, 1866) ............ 4

Schuyler Colfax,

Speech, DAILY MORNING CHRON. (D.C.)

(Oct. 28, 1868)...................................................... 5

SUMMIT CNTY. BEACON (Sep. 26, 1867) .................... 20

TIFFIN WEEKLY TRIB. (Ohio) (Aug. 16, 1866) ............. 5

USCIS,

Implementation Plan (of Executive Order

14160), IP-2025-0001 (July 25, 2025) ............... 29

vii

TABLE OF AUTHORITIES (Cont.)

Page

Vikram David Amar & Jason Mazzone,

Why the 1952 Immigration and

Nationality Act Requires the Supreme

Court to Invalidate President Trump’s

Birthright Citizenship Executive Order in

Any Event, JUSTIA (Feb. 11, 2026), https://

bit.ly/4aEoMiJ ................................................... 27

WILLIAM BLACKSTONE,

COMMENTARIES ON THE LAWS OF ENGLAND

(1765) ................................................................. 16

William Seward, Sec’y of State,

Letter to Minister to Venezuela

(Jan. 25, 1864) ................................................... 12

1

INTEREST OF THE AMICUS CURIAE1

AKHIL REED AMAR IS a constitutional scholar

and historian who seeks to aid this Court in its efforts

to practice principled constitutional decision-making

and faithful originalism. In previous briefs to this Court,

he has advanced, and today he once again advances,

positions that he has taken as an academic long before

any partisan or narrowly political implications could

have been known.

SUMMARY OF ARGUMENT

This case presents this Court a perfect opportunity

to reaffirm first principles of text, history, structure,

and precedent.

First, President Trump’s E.O. 14160 defies the

plain letter and spirit of the Fourteenth Amendment’s

first sentence, one of the crown jewels of our Constitution. In lieu of the Constitution’s grand guarantee

of equal birthright citizenship, E.O. 14160 substitutes

ad hoc rules pulled out of thin air. Constitutional

birthright citizens are citizens because of where they

are born, not to whom they are born. The Amendment

is geographic, guaranteeing equal citizenship to those

born on American soil and “under the flag,” as countless Reconstruction Republicans, led by once and

1 No party or party’s counsel authored or financially supported

any of this brief.

2

future Vice Presidents Hannibal Hamlin and Schuyler

Colfax, put the point time and again in the Amendment’s drafting and ratification process. These touchstones—the soil and the flag—cleanly explain both the

scope and the limits of the Constitution’s grand

birthright-citizenship guarantee. When a baby is born

in America and an American flag flies above the

cradle, that baby is a birthright citizen. All major

Republican leaders who carried the banner of President

Abraham Lincoln during his tenure and after his death

—including Hamlin, Colfax, Edward Bates, Salmon P.

Chase, and William Seward—shared this vision.

“Parent,” “parents,” “domicile”—these words appear

nowhere in the Amendment. If the Amendment pivoted

on any of these omitted words, as some have claimed,

enormous questions would have arisen in the

Amendment’s drafting and ratification process. How

and when would parentage and domicile be determined?

How could a parentage test ensure the rock-solid,

bullet-proof citizenship of all American-born children

of American slaves? (In the 1860s, many enslaved

parents were African-born and never-naturalized aliens,

some of whom were, technically, illegal aliens, having

been smuggled into America after 1807 by pirate

slave-traders.) No discussion of such topics in fact

occurred. That silence powerfully confirms that the

Amendment means just what it says: All persons born

inside the juridical U.S.A. and lacking diplomatic

immunity—all persons born under the flag—are born

equal citizens. It did not matter in 1868, and it does

not matter today, whether an American newborn’s

mother or father or both or neither is a U.S. citizen or

even a domiciliary; or whether either parent is Black

or White or Yellow or a so-called “Gypsy,” or was ever

3

a slave. Like the Thirteenth Amendment that precedes

it, the Fourteenth disdains hereditary-based status.

No one born in America is born a slave; and all born

squarely on the soil and under the flag are born equal

citizens.

Second, President Trump violates the Constitution’s

structure by trying to legislate enormously consequential

citizenship policies in the absence of any constitutional

provision or congressional enactment authorizing such

presidential adventurism, and indeed in defiance of

both the letter and spirit of a landmark 1952 congressional statute.

Third, E.O. 14160 flouts not one, but two of this

Court’s most venerable cases—United States v. Wong

Kim Ark, 169 U.S. 649 (1898), and Youngstown Sheet

& Tube Co. v. Sawyer, 343 U.S. 579 (1952). Both cases

faithfully followed core precepts of the Constitution

itself. By remaining true to these cases, the Court

today would also remain true to originalism.

In the spirit of candor, amicus offers below blunt

answers to the big questions raised by this case.

4

ARGUMENT

I.

What Is the Plain Meaning of the Citizenship

Clause?

The text means what it says—no more, no less:

“All persons born . . . in the United States, and subject

to the jurisdiction thereof, are citizens of the United

States.” The key initial preposition, in, is geographic.

The text says nothing whatsoever about the family to

whom a baby is born. The refining jurisdictional

clause essentially means that a baby must be born

“under the flag,” as Reconstruction Republicans put

the point at every turn. The word “under” was (and

still is) synonymous with “subject to,” and “the flag”

was (and still is) a helpfully concrete stand-in for the

more abstract word “jurisdiction.” Here, then, is the

simple and commonsense test that the Amendment

codifies and that 1860s Republicans repeated ad

infinitum: On the day a baby is born, does American

soil lie below, and does an American flag fly above?

Thus, House Speaker (and future vice president)

Schuyler Colfax declared that “every person . . . born

under our flag . . . shall have a birthright in this land

of ours.”2 Lincoln’s first vice president, Hannibal

Hamlin, likewise proclaimed that “every child born

under our flag shall be an American citizen.”3 For a

representative smattering of similar statements proclaiming that all persons born under the flag are

2 CINCINNATI COM., Aug. 7, 1866.

3 N.Y. DAILY HERALD, Oct. 6, 1866.

5

birthright citizens, see July 2 Public Letter of Speaker

Colfax, N.Y. TIMES, July 16, 1866 (“born under our

flag”) (widely reprinted elsewhere); FRANKFORT

COMMONWEALTH, July 3, 1866 (“born under the flag”);

GOLD HILL DAILY NEWS (Nev.), Aug. 17, 1866 (same);

TIFFIN WEEKLY TRIB. (Ohio), Aug. 16, 1866 (“Every

child born under our flag . . . becomes, by the very fact

of its birth beneath our flag, a citizen”); PITTSBURGH

COM., Sep. 26, 1866 (speech of General Granville

Moody) (“citizenship . . . for every one born under our

flag”); JACKSON DAILY CITIZEN (Mich.), Nov. 3, 1866

(speech of Rep. James M. Ashley) (“born under its

flag”); N.Y. DAILY HERALD, Oct. 16, 1866 (another

Hamlin speech) (“every man born under that flag shall

be an American citizen”); DAILY BEE (Cal.), June 30,

1868 (Fourteenth Amendment “declares all persons

born under the flag citizens of the United States”); and

DAILY MORNING CHRON. (D.C.), Oct. 28, 1868 (yet

another Colfax speech) (“born under the flag”). See

also CARTHAGE GAZETTE, May 3, 1866 (April 1866 speech

of Illinois Governor Richard J. Oglesby in Jacksonville)

(discussing citizenship “by virtue of . . . birth under

the flag”). Cf. AKHIL REED AMAR, AMERICA’S CONSTITUTION: A BIOGRAPHY 381 (2005) (“The amendment . . .

ma[de] clear that everyone born under the American

flag . . . was a free and equal citizen.”); id. at 351, 382,

391, 439n* (similar).4

Here, too, the basic preposition—“under”—was

geographic and place-based, not hereditary and bloodbased. Certain territorial enclaves located inside the

general geographic perimeter/footprint of the United

4 Full quotations will soon be forthcoming in amicus’s SCOTUSblog

column.

6

States fell under a different flag—most notably, quasisovereign Indian lands, foreign embassies, and land

occupied and administered under international law by

foreign armies. These enclaves lay outside the full

guarantee of constitutional birthright citizenship.

Textual analysis must heed not just what the text

says, but also what it does not say.5 Nowhere does the

text use the word “parent,” “parents,” or “domicile.” Had

it done so, the Amendment’s framers and ratifiers would

have needed to wrangle over countless complexities,

large and small, raised by these words.6 No such debates

in fact unfolded in 1866-1868—precisely because these

words and concepts were no part of the Amendment’s

letter or spirit.

If birthright citizenship depended on one’s

parentage, then would both parents matter or just

one? If one, which one? Millions of persons born in the

United States before the 1860s were born slaves

because of the slave status of their mothers, regardless

of the status of their fathers. Contrariwise, a watershed 1855 federal statute conferred citizenship on

certain babies born outside the United States if such

babies were born to certain American-citizen fathers,

regardless of the status of the babies’ mothers.7 Had

the Fourteenth Amendment’s Citizenship Clause been

5 Cf. Planned Parenthood of Se. Pa. v. Casey, 505 U.S. 833, 980

(1992) (Scalia, J., concurring in the judgment in part and

dissenting in part) (rejecting a claim because “the Constitution

says absolutely nothing about it”).

6 Cf. Caperton v. A.T. Massey Coal Co., 556 U.S. 868, 893-99

(2009) (Roberts, C.J., dissenting) (rejecting a claim that raised

countless complexities).

7 Naturalization Act of 1855, § 1, 10 Stat. 604.

7

blood-based, rather than soil-based, the Amendment

surely would have addressed the parentage issue specifically and textually, as had the 1855 statute.

If birthright citizenship depended additionally on

the allegiance of one’s parent or parents, as some

modern commentators have claimed, then would the

parental-allegiance test focus on whether the parent/

parents objectively owed allegiance in the eyes of the

government, or instead (or additionally?) on whether

the parent/parents subjectively accepted the duty of

allegiance? What if a parent or parents professed but

did not practice allegiance? What about a parent or

parents who professed and practiced allegiance even

though the U.S. government had not required such allegiance? What about children of Confederate rebels?8

What if one parent was staunchly loyal? What about

a parent of uncertain subjective allegiance at the time

a baby was born? What about a baby born to a parent

believed to be allegiant on the date of the baby’s birth

but later determined to have been nonallegiant on

that date?

And how about children born to American slavemothers? Did such mothers objectively owe or subjectively accept allegiance to a government that enslaved

them? Many antebellum theorists saw slaves as enemy

aliens—held in bondage by force—even if such “aliens”

were American-born.9 Also, countless American slavemothers were born in Africa. Some had been “legally”

8 See Samarth Desai, Birthright Citizenship: A Test Case, VOLOKH

CONSPIRACY (Feb. 18, 2025), http://bit.ly/4qpFSGK.

9 AKHIL REED AMAR, BORN EQUAL: REMAKING AMERICA’S

CONSTITUTION, 1840-1920, at 47-48 (2025) [hereinafter “BORN

EQUAL”].

8

imported to America in the late 1700s and early 1800s.

Others had been illegally pirated to America after

Congress prohibited the international slave trade in

1808. (This fact was common knowledge in 1866-1868;

President Lincoln had famously hanged an illegal slave

trader, Nathaniel Gordon, in 1862.10) How could exclusion of any babies born to American slaves be squared

with the Amendment’s central and oft-avowed purpose

of citizenizing all American-born slave children?

Procedurally, how would allegiance be determined

for any given parent? How could any process sensibly

work given the Amendment’s obvious aim of providing

a clean and ironclad rule of birthright citizenship at

the moment of birth itself?

To repeat: Virtually none of these questions was

seriously debated in the Fourteenth Amendment’s

drafting and ratification process precisely because the

text said nothing about parents—or their allegiance

or their domicile, for that matter. The text focuses on

the baby, not the parents. The text pivots on the baby’s

birth-place and not the baby’s birth-parentage. The

Amendment is a classic affirmation of jus soli, not jus

sanguinis—the law of the soil and not the law of the

blood.

The text is not only clear but also clean. Almost

any legal line can occasionally raise close questions,

but virtually all close questions raised by the Citizenship

Clause focus on geographic issues that are central to

the metes and bounds of the American constitutional

system more generally, and that thus tend to generate

decisive answers with implications far beyond birthright

10 See id. at 435-36, 494.

9

citizenship: Where does America end, and, say, Canada

or Mexico begin? In 1860s parlance, which places do

and do not operate “under the American flag?” Were

enemy forces to occupy some part of American soil and

hold it under a foreign flag, where would the edge of

occupation lie under well-recognized international law?

In the 1860s, what were the precise edges of a given

quasi-sovereign Indian enclave occupied by a tribe

that was a recognized American treaty-partner?11

By contrast, parentage opens a Pandora’s box, and

implicates devilish questions not always defined by

uniform federal law operating in other contexts. Who

are a baby’s parents? What if a mother is married to

one man, but another man is the biological progenitor?

What if there are disputes about biological parentage?

What if a baby’s biological father is unknown? What

about foundlings? In today’s world, what about a baby

born from Woman A’s egg and Man B’s sperm, who

issues from the womb of Woman C and is also claimed

by Humans D, E, and F (A’s, B’s, and C’s respective

lawful spouses)?

II. What Is the Big Idea?

Birth Equality. All Americans born under the flag

are born equal citizens.

Three great historical rivers converged in the

mid-1860s to produce this mighty constitutional text.

A careful tracing of these three rivers confirms the

11 In 1871, the U.S. permanently stopped making treaties with

Indian tribes. See 16 Stat. 544, 566. In the Indian Citizenship Act

of 1924, Congress extended birthright citizenship to babies born

on tribal lands. 43 Stat. 253.

10

plain meaning of, and the big idea animating, the

Citizenship Clause.12

The first river was Lincolnian. Its high alpine source

was the Declaration of Independence, as Lincoln and

many northern Americans came to read its grandest

phrase: “all men are created equal.” As Lincoln

understood this idea in the 1850s, it was universal,

Euclidian. But for Lincoln early on, this grand phrase

was not especially civic, not citizen-focused.

In any truly just society anywhere, Lincoln insisted,

all persons are born equally free. No one is born a slave

or born a master. All are created equal—not necessarily

in all things, but definitely in “life, liberty, and the

pursuit of happiness.” Although the Declaration of

1776 did not immediately guarantee the abolition of

slavery, Lincoln insisted that the Declaration pointed

America in precisely this antislavery direction, giving

Americans everywhere a moral north star, so that

slavery could be put on a path of ultimate extinction.

Early northern-state constitutions codified the

Declaration’s grand created-equal clause in a series of

world-changing “born equal” clauses that marked the

world’s first great abolition movement. The movement

launched with the Pennsylvania Constitution of 1776,

drafted by a convention presided over by Declaration

draftsman Benjamin Franklin, and the Massachusetts

Constitution of 1780, drafted by a convention presided

over by Declaration draftsman John Adams. The bornequal clauses of these watershed state constitutions

12 See BORN EQUAL, supra note 9, at 1-19, 297-309, 344-56, 36375, 413-76, 501-50; Akhil Reed Amar, America’s Equal Citizenship Clause, NAT’L CONST. CTR., https://constitutioncenter.org/theconstitution/amendments/amendment-xiv/clauses/700.

11

brought about the complete abolition of slavery in both

states—immediately in Massachusetts and more gradually in Pennsylvania. By 1861, fifteen of the nineteen

free states had born-equal clauses in their state constitutions, constitutions that provided strong precursors

to the opening birthright-citizenship language of the

Civil Rights Act of 1866 and its companion Fourteenth

Amendment.

For Lincoln in the 1850s, birth equality meant

equal freedom everywhere, not necessarily equal racial

citizenship anywhere. “I am not in favor of Negro

citizenship,” Lincoln proclaimed in the fourth LincolnDouglas debate in 1858.

But as president in the midst of a great Civil War,

Lincoln changed course. In September 1862, he issued

a preliminary emancipation proclamation promising

freedom for millions of Southern slaves. On January 1,

1863, he went further in his final emancipation proclamation, inviting freed slaves to join the Union army.

With this decisive pivot, Lincoln stopped conceiving of

American slaves as hereditary aliens fit for mass voluntary exodus to Africa, the supposed land of their forefathers. He now began to see them as equal birthright

Americans, entitled not just to equal freedom but to

equal citizenship. Shortly before his assassination,

Lincoln went further, laying the groundwork for equal

voting rights for Blacks.

But Chief Justice Roger Taney’s malodorous

opinion in Dred Scott threatened Lincoln’s expanding

vision of birth equality. Taney proclaimed that no

American Black could ever be a citizen—even if such

a Black were born free or became free. Taney embraced

a blood-based vision: Just as slave status was hereditary—based on the status of a baby’s mother—so too

12

citizenship status for Taney was essentially hereditary.

No Black American descended from slaves or from the

slave race, said Taney, could ever be a citizen.13

By late 1862, Lincoln’s administration openly began

to push back against blood-based and hereditarycaste-like citizenship rules. Sidestepping Dred Scott,

Lincoln’s Attorney General Edward Bates in November

1862 issued a landmark opinion basing American

citizenship on soil and not blood. Birthright citizenship,

asserted Bates in an official response to an inquiry

from Treasury Secretary (and future Chief Justice)

Salmon P. Chase, generally depended on where a

person was born. All free folk born under the American

flag were birthright citizens. “Every person born in

the country,” wrote Bates, “is, at the moment of birth,

prima facie a citizen . . . without any reference to race

or color, or any other accidental circumstance.”14 In

an earlier memo to Secretary of State William Seward,

Bates was absolutely emphatic on the precise question

at the heart of today’s dispute: “Children born in the

United States of alien parents, who have never been

naturalized, are native-born citizens of the United

States.”15 In official correspondence in 1864, Seward

himself echoed Bates: “[T]he children of foreigners

born here are citizens of the United States.”16 Chase,

13 Dred Scott v. Sandford, 60 U.S. (19 How.) 393, 403, 407, 41112 (1857).

14 Edward Bates, Att’y Gen., Op. of Att’y Gen on Citizenship

(Nov. 29, 1862).

15 Memorandum from Edward Bates, Att’y Gen., to William Seward,

Sec’y of State (Sep. 1, 1862) (available online) (emphasis added).

16 Letter to Minister to Venez. (Jan. 25, 1864) (available online)

(emphasis added).

13

too, enthusiastically echoed Bates’s opinion: “[A]ll free

persons born in the United States or naturalized of

whatever color, are citizens of the United States.”17

At war’s end, Reconstruction Republicans in Congress squarely sided with the party’s leading lights—

Lincoln, Bates, Chase, and Seward—in a watershed

1866 Civil Rights Act that opened as follows: “[A]ll

persons born in the United States and not subject to

any foreign power, excluding Indians not taxed, are

hereby declared to be citizens of the United States.”18

But would a mere executive memo and a simple

congressional statute suffice? What if the Supreme

Court tried to resurrect Taney’s Dred Scott opinion and

declare the memo and the statute unconstitutional?

What if some future president tried to rescind the

memo or ignore the statute?

In the late 1860s, America adopted a constitutional

amendment to settle the matter conclusively. The

Amendment opened with language echoing and tweaking the watershed statute: “All persons born or naturalized in the United States, and subject to the jurisdiction

thereof, are citizens of the United States.” This of

course is the very sentence at the heart of today’s case.

A second great historical river feeding the eventual

Fourteenth Amendment flowed through English common law. Under rulings going back centuries, including

most famously Calvin’s Case in 1608, 77 Eng. Rep.

17 James P. McClure, et al., eds., Circumventing the Dred Scott

Decision: Edward Bates, Salmon P. Chase, and the Citizenship of

African Americans, 43 CIV. WAR HIST. 279, 279 (1997) (emphasis

added).

18 Civil Rights Act of 1866, 14 Stat. 27.

14

377, English jurists had made clear that a baby born

on English soil was almost invariably born an English

subject, even if her parents were, say, French folk

sojourning in England. A high-profile antebellum New

York opinion, Lynch v. Clarke, 1 Sand. Ch. 583 (N.Y.

Ch. 1844), relied on English jurisprudence to hold that

a baby born in New York to noncitizen parents was

indeed a birthright New York citizen. Bates himself

relied on Lynch and also relied on venerable English

caselaw, including Calvin’s Case.19

A third river involved the imperative political

needs of the Republican Party after 1865. Slavery’s

abolition meant that the three-fifths rule that previously

had applied to slave apportionment would now swell

into a five-fifths rule for newly freed slaves; thus,

unless other changes were made, the former Confederate

states would re-enter Congress with even more seats

than before. Republicans decided that if ex-Confederate

states were to count Blacks at a full five-fifths, then

Black men in these states needed to be enfranchised.

Republican leaders also understood that newly enfranchised freemen would likely vote for the party that

had voted for them—namely, the Republican Party,

Lincoln’s party, the party that had won the war and

now needed to win the peace.

To secure reliable Black voting in the South,

Republicans needed bulletproof rules guaranteeing

Black birthright citizenship—soil-based rules, clean

and clear rules that focused on where a person was

19 English jurisprudence had been an awkward inheritance for

some Southern antebellum Whites. Only after American slavery

was abolished did America closely approximate England, which

had never experienced widespread slavery on its home soil.

15

born and not fuzzy rules focusing on parentage or

parental allegiance or parental domicile. Republicans

never aimed to allow ex-Confederate states to deny the

vote to various Black men because these men had been

born to slave mothers or slave fathers who in turn had

been born in Africa. Countless American freedmen were

indeed born to enslaved parents who themselves were

not citizens when their babies were born. Many of

these parents were not only African-born and nevernaturalized aliens; they were African-born and nevernaturalized illegal/undocumented aliens, having been

smuggled into America after 1807 in violation of

American law prohibiting international slave importation. Republicans aimed to citizenize the children of

all such aliens—no ifs, ands, or buts.20

20 Professor Lash has recently emphasized that illegal-alien

slaves in America circa 1866 had typically come to the U.S.

unwillingly. See Kurt T. Lash, Prima Facie Citizenship: Birth,

Allegiance and the Fourteenth Amendment’s Citizenship Clause,

101 NOTRE DAME L. REV. (forthcoming 2026). But here is a

conversation that never unfolded in 1866-1868: Prominent

person X said that a baby born on the soil and under the flag

needed to have a parent who was herself/himself either a lawful

citizen or an alien lawfully and permanently present; prominent

person Y then countered that such a rule would make no sense

for aliens illegally smuggled into the U.S. through no fault of

their own; and then Y or prominent person Z discussed the

myriad birthday-adjudication complexities that would arise if

the voluntariness of the parents’ presence on American soil were

the key question. Contra Lash, the letter and spirit of the

Birthright Citizenship Clause clearly focused on the baby, not the

parent.

True, Congressman John Bingham once said—in a passage Lash

quotes eight times—that “every human being born within the

jurisdiction of the United States of parents not owing allegiance

to any foreign sovereignty is, in the language of your Constitution

itself, a natural-born citizen.” CONG. GLOBE, 39th Cong., 1st Sess.

16

III. What Does the Phrase “Subject to the

Jurisdiction” Mean and What Does It Not

Mean?

As previously explained and as well-elucidated in

United States v. Wong Kim Ark, 169 U.S. 649 (1898),

it essentially means “under the flag” and codifies

ancient English and British common law, as adapted

to America.

A baby born on American soil under an American

flag is typically subject to ordinary American law in

the ordinary way—subject, that is, to American jurisdiction. Modern examples of such laws include vaccine

laws and birth-certificate laws.

As an island, England had long prided itself on

the special rules that applied to English soil.21 At

1291 (Mar. 9, 1866) (emphasis added). Lash fails to highlight

that Bingham immediately corrected himself, referring later in

the very same sentence to “any man born within the jurisdiction

of the United States, not [himself!—with no reference to parents]

owing a foreign allegiance.” Id. In any event, Bingham’s misstatement sharply deviated from: (1) the text of the bill he was

trying to expound, which said nothing of parents; (2) ancient

British common law governing children of foreign sojourners

born in Britain; (3) the Bates memo that Bingham was

essentially seeking to codify; and (4) Bingham’s own statements

on later occasions, see, e.g., infra p. 20. The Bingham

misstatement of course also deviates sharply from E.O. 14160,

which accepts the birthright citizenship of babies born to greencard holders who, as foreign nationals, do indeed owe allegiance

to foreign sovereignties.

21 For example, Blackstone’s COMMENTARIES gushed that the

“spirit of liberty is so deeply . . . rooted even in our very soil, that

a slave or a negro, the moment he lands in England . . . becomes

a freeman,” at least with regard to “the protection of the laws.” 1

BLACKSTONE, COMMENTARIES *126-27.

17

least since the early 1600s, and perhaps much earlier,

all babies born on English soil were generally seen as

English subjects by birth, even if born to alien parents

merely passing through England. The largest numerical

exception to birthright status in England was likewise

territorial: various babies born behind occupied enemy

lines were not automatically birthright English subjects.

For broadly similar reasons, the Fourteenth Amendment

also withheld birthright citizenship from those born

on quasi-sovereign Indian land. Section Two of the

Amendment refers in closely related language to

“Indians not taxed.”

Also, in both England and America, those born as

children of foreign diplomats did not automatically

enjoy birthright status. This tiny wrinkle was conceptualized in several ways. First, a diplomat and his child

were seen as floating human chunks of foreign soil,

with partial or total diplomatic immunity from America’s laws.22 Second, a baby born to a diplomat was

treated as if she were born inside the embassy—

foreign soil under a foreign flag, akin to foreign-occupied

territory or a foreign public vessel.23 Third, this wrinkle

could be understood as a force-majeure concession to

non-English, non-American regimes that would have

reacted with anger, perhaps war, had the children of

their diplomats been treated as English or American

22 See, e.g., CONG. GLOBE, 39th Cong., 1st Sess. 1124 (Mar. 1,

1866) (statement of Rep. Burton Cook); id. at 2897 (May 30,

1866) (statement of Sen. George Williams).

23 See id. at 2769 (May 23, 1866) (statement of Sen. Benjamin

Wade) (elaborating the “fiction of law” underlying the wrinkle);

H. W. HALLECK, INTERNATIONAL LAW 209 (1861) (discussing the

“fiction of extraterritoriality”).

18

subjects or citizens rather than in effect, personal extensions of, say, the King of France or the Tsar of Russia.

The diplomat’s-child wrinkle generated very little

discussion in the mid-1860s. For starters, the wrinkle

was well-settled in England. By contrast, excluding

children of lawful foreign sojourners born in America

from birthright citizenship—the very rule propounded

by E.O. 14160—would have sharply broken with English

common law. Had such a radical rule been urged in the

mid-1860s, it would have precipitated massive discussion and pushback. Also, the diplomat’s-child wrinkle

was numerically trivial. It “could hardly be applicable

to more than two or three or four persons,” declared

Republican Senator Benjamin Franklin Wade.24 Moreover, the diplomat’s-baby wrinkle nicely avoided several

of the thorny issues raised by American-born children

of foreign sojourners more generally. On the how-many

parents and the which-parent questions: Obviously,

the status of the diplomatic parent would govern. On

the who’s-your-daddy question: Obviously, the wrinkle

applied only to babies claimed by a diplomat.

Twenty-first-century immigration skeptics invoke

the “subject to the jurisdiction” clause as if it captured

and solved several modern-day policy objections to the

plain letter and spirit of the Fourteenth Amendment’s

general birthright command. But these skeptics in

fact twist the jurisdiction clause into a pretzel, torturing

it to carry meanings that its words and history cannot

bear.

First, immigration skeptics dislike “rewarding”

illegal/unauthorized immigrants by citizenizing their

24 CONG. GLOBE, 39th Cong., 1st Sess. 2769 (May 23, 1866).

19

American-born children. But as amicus has repeatedly

stressed, the text—both the main “born in” birthright

guarantee and the jurisdiction-clause refinement—is

about the baby, not the parent. If parents have broken

the rules, then America can lawfully impose harsh

civil and criminal sanctions on them. America also has

many economic and diplomatic tools to sanction those

who aid and abet illegal/unauthorized immigrants,

both inside and outside America. But America may

not punish children for the wrongs of their parents.

Decitizenizing is indeed attempted punishment, precisely because the legal baseline of the Fourteenth

Amendment clearly makes babies born on American

soil under the American flag American citizens, regardless of who their parents are or what their parents

have done.

Second, modern immigration skeptics stretch the

occupying-army analogy beyond recognition. The key

concepts here are occupying and army. Even if one

thinks that, say, Houston or LA or Minneapolis is being

“invaded” by aliens, these cities are emphatically not

being occupied by foreign forces, as these latter two

italicized words were understood in pre-1860s international-law scenarios—involving, for example, British

troops in certain parts of America in the 1810s, and

American troops in certain parts of Mexico in the 1840s.

Third, immigration skeptics dislike so-called “birth

tourism”—whereby persons lawfully in the United

States as students, sojourners, etc., give birth to

babies in the U.S. Here, too, the U.S. government may

properly respond by limiting the noncitizen parents in

myriad ways. But the government cannot decitizenize

American-born children.

20

In sum: The words “subject to the jurisdiction”

simply have nothing to do with the policy concerns of

modern immigration skeptics.

When asked whether a precursor statute to the

Fourteenth Amendment, which had a more broadly

worded “jurisdiction” clause, would citizenize “the children of Chinese [aliens] and [proverbially roaming,

nondomiciliary, so-called] Gypsies born in this country,”

Republican Senator Lyman Trumbull replied with a

single emphatic word that speaks volumes: “Undoubtedly.”25 Representative John Bingham used similarly

robust language on the campaign trail in 1867: “If a

man is not a citizen of the country in which he was

born, in God’s name of what country is he a citizen?”26

IV. What Do This Court’s Relevant Fourteenth

Amendment Precedents Say?

Beginning with Wong Kim Ark, a long line of

Supreme Court precedents tightly aligns with the

arguments and evidence that amicus presents today.

25 CONG. GLOBE, 39th Cong., 1st Sess. 498 (Jan. 30, 1866)

(emphasis added); see also id. at 2891 (May 30, 1866) (statement

of Sen. John Conness) (defending, in a similarly emphatic

statement, the plain meaning of the Fourteenth Amendment’s

birthright-citizenship guarantee to American-born babies of

Chinese aliens).

26 SUMMIT CNTY. BEACON, Sep. 26, 1867. For a brilliant analysis

of proverbially nondomiciliary and, in England, illegal-alien

“Gypsies” more generally, and a great discussion of why the socalled “Gypsy” example is uniquely powerful in refuting various

theories underlying E.O. 14160, see Gerard N. Magliocca, Without

Domicile or Allegiance: Gypsies and Birthright Citizenship, 49

HARV. J.L. & PUB. POL’Y 539 (2026).

21

The Court’s rule and rationale in Wong Kim Ark

are clear as day:

[B]y the law of England for the last three

centuries, beginning before the settlement of

this country, and continuing to the present

day, . . . every child born in England of alien

parents was a natural-born subject, unless

the child of an ambassador or other diplomatic

agent of a foreign state, or of an alien enemy

in hostile occupation of the place where the

child was born. The same rule was in force in

all the English colonies upon this continent

down to the time of the Declaration of Independence, and in the United States afterwards, and continued to prevail under the

constitution as originally established. . . . In

the forefront, both of the fourteenth amendment of the constitution, and of the civil

rights act of 1866, the fundamental principle

of citizenship by birth within the dominion

was reaffirmed in the most expl[i]cit and

comprehensive terms.

169 U.S. at 658-75 (emphases added).

Because many other briefs have already covered

and many more will likely continue to cover Wong Kim

Ark and its progeny27 in detail, amicus shall simply

27 See, e.g., Weedin v. Chin Bow, 274 U.S. 657, 660, 670 (1927);

Morrison v. California, 291 U.S. 82, 85 (1934); Hirabayashi v.

United States, 320 U.S. 81, 96-97 (1943); United States ex rel.

Hintopoulos v. Shaughnessy, 353 U.S. 72, 73 (1957); INS v.

Errico, 385 U.S. 214, 215-16 (1966); Plyler v. Doe, 457 U.S. 202,

211 n.10 (1982); INS v. Rios-Pineda, 471 U.S. 444, 446 (1985); see

also Trump v. CASA, Inc., 606 U.S. 831, 885-86 (2025) (Sotomayor,

J., dissenting) (collecting cases).

22

underscore three key points that deserve special

mention.

First, Wong Kim Ark deserves extra precedential

weight because it is an originalist decision strongly

rooted in the Fourteenth Amendment’s text and

enactment history, and also in centuries-old English

caselaw and high-profile antebellum American caselaw

that informed that Amendment. Cf. Dobbs v. Jackson

Women’s Health Org., 597 U.S. 215, 264-65, 278 (2022).

Second, the author of the dissent, Chief Justice

Melville Fuller, had been a staunch Democrat in the

1860s who had consistently opposed Lincoln’s Republican Party. Republicans had pushed through the Fourteenth Amendment in a sharply polarized vote. Not a

single congressional Democrat voted for the Amendment

when it cleared the House and Senate in 1866.28 Fuller

was thus never the best source for a faithful account

of the Amendment’s letter and spirit.29

Third, although the great John Marshall Harlan

joined Fuller’s dissent, Harlan himself had stumbled

badly in one notable passage of his otherwise admirable

Plessy v. Ferguson dissent, authored only two years

before Wong Kim Ark. Because this Plessy passage

was plainly wrong on the law, and because it also

hints at possible anti-Asian bigotry on Harlan’s part,

today’s Court should think twice before invoking Harlan

on the specific birthright-citizenship issue now before

the Court.

28 BORN EQUAL, supra note 9, at 516, 697 n.31; AKHIL REED AMAR,

AMERICA’S UNWRITTEN CONSTITUTION: THE PRECEDENTS AND

PRINCIPLES WE LIVE BY 399 (2012).

29 BORN EQUAL, supra note 9, at 553.

23

Harlan in Plessy claimed that “there is a race so

different from our own that we do not permit those

belonging to it to become citizens of the United

States. . . . I allude to the Chinese race.”30

Not true. Imagine two ethnic-Chinese persons—

that is, two members of “the Chinese race,” in Harlan’s

phrase—one male and one female, each born in Africa

in 1850. (There were in fact countless ethnic Chinese

in Africa in this era.) Imagine further that these two

persons migrated to America in 1871, married each other

in 1872, and naturalized in 1873. Congress’s Naturalization Act of 1870 quite expressly authorized our hypothetical newlyweds to naturalize as “aliens of African

nativity”—as pointedly distinct from persons of “African

descent,” addressed separately in the 1870 Act.31 Thus,

contra Harlan, American law circa 1896 did permit

“those belonging to” the “Chinese race” to “become

citizens of the United States.”

Now imagine that our hypothetical couple gave

birth to a baby born in San Francisco in 1876, America’s

centennial year. As an American-born child of two

naturalized American citizens, our centennial baby

would have undoubtedly been a birthright citizen under

any definition of the Fourteenth Amendment (even

President Trump’s!). Surely the Fourteenth Amendment contains no racial bar as such, contra Harlan.

Harlan faltered in this key Plessy passage; his

closely related dissenting vote in Wong Kim Ark

should thus be sharply discounted.

30 163 U.S. 537, 561 (1896) (Harlan, J., dissenting).

31 Naturalization Act of 1870, 16 Stat. 254 (emphasis added).

24

V.

What Do Leading Fourteenth Amendment

Scholars Say?

The overwhelming consensus of expert scholars

strongly supports amicus’s claims that the Fourteenth

Amendment’s first sentence means what it says; that

the refining phrase “subject to the jurisdiction” has

virtually nothing to do with an American-born baby’s

parents’ allegiance or domicile or immigration status

or law-abidingness; and that Wong Kim Ark got it

right. Amicus does not today impugn the good faith of

the handful of scholars who have taken a contrary

position. But as a scholar who has studied the Fourteenth Amendment for decades, amicus candidly reports

to this Court that much of the contrarian scholarship

is plainly wrong.

VI. What Should the Court Make of the Solicitor

General’s Petitioner Brief?

Petitioner ignores what the Amendment says—

its obvious focus on geography, with its words “in” and

“jurisdiction.”

Petitioner ignores what the Amendment omits—

words such as “parents,” and “domicile.” Petitioner reads

these elephantine words into the Amendment based

on mousehole-size snippets wrenched from context.

In an unintentionally self-defeating footnote,

Pet.Br.18 n.4, Petitioner quotes Senator Lot Morrill

and Representative John Broomall, and strongly implies

that these two emphasized the allegiance of a baby’s

parents. In fact, both men focused entirely on the

baby’s allegiance, not the parents’. Petitioner’s Broomall

quote indeed says it all: “What is a citizen but a

human being who by reason of his being born within

25

the jurisdiction of a Government owes allegiance to

that Government?”32 Morrill said the same thing in

the very sentence preceding the one quoted by Petitioner:

“[E]very man, by his birth, is entitled to citizenship,

and . . . owes allegiance to the country of his birth.”33

Petitioner also relies on a verbal slip in which

Congressman Bingham carelessly used the word

“parents.” Pet.Br.17. But see supra note 20.

Petitioner likewise quotes a private letter allegedly

by Senator Trumbull using the word “parents”—a

letter at odds with what Trumbull said emphatically

and publicly on the Senate floor, in an important

exchange unmentioned by Petitioner.34

In a misleading and garbled passage, Pet.Br.24,

Petitioner quotes a stray question posed by Senator

William Fessenden to Senator Benjamin Wade on May

23, 1866,35 and then uses this quote to imply that the

“subject to the jurisdiction” language aimed to exclude

from citizenship American-born children of foreign

sojourners generally. Wrong. The “subject to” verbiage

was first introduced six days and one hundred CONGRESSIONAL GLOBE pages after Fessenden’s stray question,

and had nothing to do with Fessenden or with the

32 CONG. GLOBE, 39th Cong., 1st Sess. 1262 (Mar. 8, 1866)

(emphasis added).

33 Id. at 570 (Feb. 1, 1866) (emphasis added).

34 Compare Pet.Br.24; with CONG. GLOBE, 39th Cong., 1st Sess.

498 (Jan. 30, 1866).

35 CONG. GLOBE, 39th Cong., 1st Sess. 2769.

26

general issue of American-born children of foreign

visitors.36

Again: In pointedly omitting the words “parents”

and “domicile,” the Reconstruction Congress aimed to

codify the sweeping birth-equality precepts of the

Lincoln Administration, as articulated by Bates, Chase,

and Seward, backed by a high-profile state-court

ruling and centuries of English jurisprudence tracing

back to 1608. Had the Amendment aimed to repudiate

these grand precursors, such a repudiation would

have raised elephant-sized problems and generated a

massive debate. But such a great debate never

happened.

Petitioner’s brief instead presents the Court an

artful pastiche of misleading, misinterpreted, and/or

atypical shards.37

36 Id. at 2869 (May 29, 1866) (statement of Sen. Howard)

(introducing the final version of the Citizenship Clause). Contra

Petitioner: Wade never introduced a standalone citizenship clause

as such; nor was any Wade-authored language ever agreed to;

nor did the “subject to” language directly revise a previously

agreed-upon Wade-authored citizenship clause. Rather, long

after the Wade-Fessenden exchange, Howard added a single twopart Citizenship Clause restating basic soil-based principles

(“born in”) and longstanding under-the-flag limits and wrinkles

(“subject to”). These longstanding wrinkles and limits had

nothing whatsoever to do with American-born children of alien

travelers.

37 In confronting something as vast as the Fourteenth

Amendment, one can always find some careless, confused, or

contrarian statements by someone. Cf. Murphy v. Smith, 583

U.S. 220, 228 n.2 (2018) (Gorsuch, J.) (finding Petitioner’s

legislative-history snippets insufficient to overcome the enacted

text and surrounding context).

27

More generally, Petitioner misses the Amendment’s

grand vision of birth equality under the flag. At the

margins, Petitioner aims to make our Constitution

more heredity-based, more caste-like.

On a different front: Petitioner nowhere confronts—

nowhere even mentions—this Court’s celebrated decision

in Youngstown, which forbids presidents from ruling

by executive fiat and also obliges presidents to heed

valid congressional statutes. Petitioner tries to sidestep these issues by claiming that the 1952 Immigration

and Nationality Act (INA) mirrors the Fourteenth

Amendment as Petitioner now misconstrues that

Amendment, more than 150 years after the Amendment’s enactment and nearly 75 years after the INA’s

passage. But of course in 1952, Congress built upon

the Amendment as definitively glossed by this Court

in Wong Kim Ark and its progeny. Even were Wong

Kim Ark today thought by Petitioner or Petitioner’s

amici to be erroneous, Congress thought otherwise in

1952 and legislated on that basis.38 Petitioner points

to no substantial contemporaneous evidence suggesting

that Congress, the legal community, or the public at

large in 1952 generally rejected Wong Kim Ark or

that Congress aimed to sneak into its own statutory

language a hidden time bomb set to explode decades

later.

And speaking of Wong Kim Ark . . . Petitioner

fails to carry the heavy burden of showing, as a matter of

38 See Vikram David Amar & Jason Mazzone, Why the 1952

Immigration and Nationality Act Requires the Supreme Court to

Invalidate President Trump’s Birthright Citizenship Executive

Order in Any Event, JUSTIA (Feb. 11, 2026), https://bit.ly/

4aEoMiJ.

28

stare decisis doctrine, that Wong Kim Ark and the long

line of cases building on this landmark precedent are

clearly wrong on originalist grounds. See Dobbs, 597

U.S. at 268, 269-70, 278. Nor does Petitioner adduce

any other compelling reason for the Court today to

abandon this well-settled and well-respected line of

cases.

VII. How Does President Trump’s Executive

Order Fare Under Marbury and Youngstown?

Miserably. In Marbury v. Madison, 5 U.S. (1

Cranch) 137, 154-73 (1803), the Court stood up to the

president even more than it stood up to Congress.

Back then, President Jefferson was acting unconstitutionally by refusing to recognize one single American’s

vested commission. Today, President Trump is acting

unconstitutionally by refusing to recognize millions of

future Americans’ vested citizenship rights.

Even worse, President Trump is trying to do this

with no congressional statute authorizing his actions

and indeed in defiance of the clear language of the

1952 INA, 8 U.S.C. § 1401(a), guaranteeing citizenship

to any “person born in the United States, and subject

to the jurisdiction thereof.”

Assume arguendo that the Fourteenth Amendment

—either standing alone or as glossed by Wong Kim

Ark—somehow did not citizenize all babies born in

America under the flag. The 1952 statute itself surely

did just that—not just because of the plain meaning of

§ 1401(a) standing alone, and not just because the

statute obviously incorporates Wong Kim Ark, but also

because any other reading makes a hash of the INA’s

overall linguistic structure. Several sections of the 1952

INA featured detailed rules regarding “father[s]” and

29

“mother[s]” of various babies born beyond America’s

soil and flag,39 but § 1401(a) pointedly omitted these

words and counterpart words such as “parent.” President Trump offers no substantial evidence that Congress, the executive branch, the judiciary, or the

American people in 1952 generally thought that the

INA’s words meant anything close to the rules he is now

laying down by executive decree. And while Congress

has modified many other sections of the naturalization

code since 1952, Congress has never reworded the

iconic § 1401(a).

VIII. What Should the Court Make of the

Various Lines Drawn in E.O. 14160?

The details of E.O. 14160 are made-up and slapdash. This is what pure diktat looks like.

Even were it somehow proper to penalize Americanborn children of aliens illegally present in the U.S.,

what part of the Fourteenth Amendment or the 1952

Act says that American-born children of aliens who

hold lawful visitor visas or lawful student visas or

lawful immigrant visas or lawful business visas are

somehow lesser than American-born children of aliens

who have green cards? Why does the E.O. use different

language in describing “father[s]” and “mother[s]?” See

§ 2(a).40 Why must a father be “biological?” See § 4(b).

39 See 8 U.S.C. §§ 1101(b), 1403(a), 1403(b). For later-enacted

provisions making similar parental distinctions, see, for example,

8 U.S.C. § 1409(a)(1)-(4).

40 For example, a nontemporary alien mother with asylum or

refugee status is apparently treated differently from a nontemporary

alien father with such status. See USCIS, Implementation Plan

(July 25, 2025).

30

DNA tests did not exist in the 1860s, and background

legal understandings in that era would generally have

treated the legal husband of the mother as the legal

father, regardless of biology.

If today’s president can make up rules one way,

can tomorrow’s president reverse everything? Can

tomorrow’s president go even further in the opposite

direction? What about the president after that, and so

on? Would voting rights for federal elections swing

wildly back and forth every few years?

IX. Why Should the Court Decide the Big

Constitutional Question of Birthright

Citizenship When Off-Ramps Are Available?

A ruling that strikes down E.O. 14160 simply on

the Youngstown ground that the president cannot

unilaterally dictate citizenship rules (Justice

Jackson’s Category 2) or on the Youngstown ground

that a president cannot defy the clear 1952 congressional statute (Justice Jackson’s Category 3) would

fail to do full justice to relevant rightsholders—in

other words, would fail to fully remedy the gross

constitutional violation that E.O. 14160 attempts.

Imagine a little girl named Sandra Ruth Marshall

born in El Paso or Brooklyn on July 4, 2026, to two

parents who are not green-card holders or citizens.

Sandra Ruth Marshall is entitled to know from the

very beginning of her life not just that she is an

American citizen, but also that she is a constitutional

birthright citizen. She is entitled to know that not

even a future congressional statute can deprive her of

her vested constitutional right should Congress one

day try to retroactively repeal the 1952 Act.

31

The scope and depth of this right should be declared

by this Court—Marbury-style, Brown-style—not just

for Sandra Ruth Marshall’s benefit but also for the

benefit of all the rest of us, so that we, too, may fully

understand our constitutional rights, responsibilities,

and relationships. Citizenship rights are not merely

individual rights against government. Citizenship

creates horizontal rights and relations among and

between citizens themselves. Tellingly, the Fourteenth

Amendment speaks of “citizens” in the plural, even

though this plural created a grammatical glitch. (The

text speaks of “the state” in which “they”—the

“citizens”—“reside” even though, of course, different

citizens reside in different states, with an s.) Citizenship

involves more than liberty (bodily freedom from forced

deportation) and equality. Citizenship also implicates

civic fraternity. American citizens rightly owe each

other special respect and can rightly claim from each

other special solicitude.

X.

Why Is This the Most Important Case of the

Century (So Far)?

Three reasons.

First, this case is uniquely easy. The central

constitutional issue of equal birthright citizenship is

clear; plus, there is no executive authority to act

unilaterally here; plus, the President’s gerrymandered

E.O. clearly violates a congressional statute of long

standing, a statute that no court has ever read to mean

anything remotely close to E.O. 14160. Proverbially,

hard cases make bad law. Easy cases can make even

worse law if they err. Gross error in an easy case leads

to corrosive public cynicism and indeed threatens the

32

very rule of law. A wrong ruling in this case would be

eerily reminiscent of Dred Scott v. Sandford.

Second, this case is uniquely fundamental. A

wrong ruling would not just be egregious. It would be

enormous. The basic issues at stake go to the very

foundation of the Constitution. At root, citizenship is

the right to have rights, and the right to belong. All

constitutional issues are important, but few rival the

constitutional issues in this case: Who is an American?

May a president ignore the Constitution itself? May a

president defy valid congressional statutes and make

himself a dictator of all law?

Third, a correct ruling in this case would give this

Court a once-in-a-lifetime opportunity. This is a unique

Marbury-meets-Youngstown-meets-Brown-meets-Nixon

Tapes moment. America and the world need to see

what amicus sees: that the Court is not merely a group

of politicians in robes.

Amicus thus hopes the Court will not just rule the

right way in this case, but will do so for the best and

deepest reasons—ringingly—and will also do so unanimously, at least in outcome, and ideally in exposition.

33

CONCLUSION

Today is not the day for this Court to go small in

saying what the law is. Today is a day for this Court

to proudly proclaim that all persons born on American

soil and under the American flag are Americans—

truly, are citizens; are birthright citizens; are equal

citizens; and indeed are constitutionally equal birthright

citizens.

Respectfully submitted,

Vikram David Amar

Counsel of Record

UNIVERSITY OF CALIFORNIA,

DAVIS SCHOOL OF LAW*

400 Mrak Hall Drive

Davis, CA 95616

(925) 858-8855

vdamar@ucdavis.edu

Counsel for Amicus Curiae

February 23, 2026

* University affiliation provided for identification purposes only.