Defining Citizenship: Ozawa, Thind, And Today’s Debate Over Birthright

by Mofe Koya, Associate Member, University of Cincinnati Law Review Vol. 94

I. Introduction

The question of who qualifies as an American citizen has shaped constitutional interpretation for over a century. United States v. Wong Kim Ark (1898)¹ firmly established birthright citizenship under the Fourteenth Amendment, yet later cases such as Ozawa v. United States (1922)² and United States v. Thind (1923)³ revealed how flexible, yet exclusionary, the concept of belonging could become. The concept of belonging in the United States has become especially relevant following the issuance of President Donald Trump’s Executive Order aimed at limiting the constitutional protection extended to children of immigrants. In Barbara v. Trump (2025), the plaintiff class’ challenges to Trump’s Executive Order restricting birthright citizenship signal a return to the issues upon whichOzawa and Thind rested on: who counts as “one of us”? These cases collectively demonstrate the Supreme Court’s recurring struggle to define American citizenship. While the overtly racial logic of the early twentieth century has been replaced by distinctions grounded in jurisdiction and legal status, the underlying impulse to police who belongs, persists. This Article argues that understanding this historical through-line is critical for the Court as it considers the constitutionality of modern limits on birthright citizenship.

This Article will explore the history of citizenship and naturalization in the United States. Part II will discuss the constitutional framework establishing the fundamental right of birthright citizenship in the United States and analyze the cases that followed. The conflicting decisions in Ozawa and Thind, defined race as a construct when it came to naturalization eligibility and set a precedent of arbitrary definitions that undermined the stability of citizenship. It will then address contemporary issues regarding the redefinition of citizenship eligibility as it relates to modern debates surrounding birthright citizenship. Part III will argue that fluctuating definitions weaken the rule of law and erode constitutional trust and contend that the Court must not continue to follow that pattern of allowing social or political considerations to override clear constitutional text. Lastly, Part IV will summarize this discussion and emphasize the need for an inclusive interpretation of citizenship that honors the original intentions of the Fourteenth Amendment.

II. BACKGROUND

The tension between legal protections and racial considerations consistently shaped the concept of citizenship in the United States throughout history. This section provides a foundational overview of the legal and historical framework necessary to understand contemporary debates over birthright citizenship.

A. The Constitutional Framework

The Fourteenth Amendment opens with the Citizenship Clause and guarantees, “[a]ll persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside.”⁴ The Supreme Court addressed the reach of the Citizenship Clause in United States v. Wong Kim Ark.⁵ Wong was born in San Francisco to parents who were both Chinese citizens but resided in the United States at the time of his birth.⁶ At age 21, Wong took a trip to China to visit his parents and was denied entry back into the United States upon his return.⁷ Detained on steamships in San Francisco Bay for months, Wong took his case to the courts.⁸

The question before the Court became,

[W]hether a child born in the United States, of parents of Chinese descent . . . but have a permanent domicile and residence in the United States . . . becomes at the time of his birth a citizen of the United States by virtue of the first clause of the Fourteenth Amendment of the Constitution.⁹

In a 6-2 decision, the Court ruled in favor of Wong, holding that because he was born in the United States and his parents were not “employed in any diplomatic or official capacity under the Emperor of China,” the Citizenship Clause of the Fourteenth Amendment automatically made him a United States citizen.¹⁰ Wong Kim Ark affirmed the fundamental right of birthright citizenship for children of all immigrants regardless of the parent’s immigration status.¹¹

B. Early Racial Constructions of Naturalization

While Wong Kim Ark affirmed that birth on United States soil guaranteed citizenship, the decision did not answer another question that became increasingly contested—who is capable of becoming American in the first place? In the decades that followed, cases like Ozawa v. United States and United States v. Thind tested the limits of citizenship not by birthplace, but by race. Together, they revealed how legal definitions of belonging could shift with prevailing social attitudes, even when constitutional language remained fixed.

1. Ozawa v. United States

In October 1922, the Supreme Court heard Ozawa v. United States.¹² Takao Ozawa, a Japanese immigrant living and working in Hawaii with his family sought United States citizenship.¹³ Ozawa had lived in the United States for over twenty years and had, by all accounts, fully embraced American culture.¹⁴ He spoke English, sent his children to American schools, attended an American church, and married a wife educated in the United States.¹⁵ Although Ozawa met every other qualification for citizenship, his application was denied solely because of his race.¹⁶ The U.S. District Attorney for the District of Hawaii argued that Ozawa was of the “‘Japanese race’ and therefore not a ‘white person.’”¹⁷ The Supreme Court agreed unanimously, reasoning that because all Naturalization Acts from 1790 to 1906 restricted naturalization to “free white persons,” Ozawa was ineligible for citizenship.¹⁸

Ozawa, who was paler than the average white person, asserted that despite his Japanese descent, his skin color made him “white.”¹⁹ In his brief to the Court, Ozawa included quotes from different anthropological observers citing that, “the Japanese are of lighter color than other Eastern Asiatic, not rarely showing in the transparent pink tint which whites assume as their own privilege” and “in the typical Japanese city of Kyoto, those not exposed to the heat of the summer are particularly white-skinned.”²⁰ The Court rejected this assertion reasoning that the meaning of the words “white person” could not be determined by the mere color of skin.²¹ The opinion, authored by Justice George Sutherland, further explained that, “even among Anglo-Saxons [skin color ranges] by imperceptible gradations from the fair blond to the swarthy brunette . . . [h]ence to adopt the color test alone would result in confused overlapping of races and a gradual merging of one into the other, without any practical line of separation.”²² Justice Sutherland also clarified the difference between the meaning of the term “white persons” and “Caucasian” determining that the latter, “although more inclusive than the former, is not so inclusive as to encompass persons of Asian extraction.”²³

The Ozawa decision not only reinforced racial animosity toward Japanese immigrants in the United States but also marked the Court’s acceptance of a so-called “scientific” approach to racial classification.²⁴ At the time, anthropologists divided humanity into four physical groupings: Caucasian, Mongolian, Negroid, and Amerind. Science classified Ozawa as Mongolian, and thus the Court concluded that he could not be considered “white.”²⁵ In doing so, the Court endorsed the notion that race could be objectively determined through pseudoscientific taxonomy.²⁶

2. United States v. Thind

Just a few months after the Ozawa decision, the Supreme Court decided United States v. Bhagat Singh Thind.²⁷ Thind, born in India and a graduate of Punjab University, arrived in the United States when he was twenty-one years old in 1913.²⁸ The United States saw a new wave of Asian immigrants by 1920.²⁹ This new group “differed in an important respect from other Asian immigrants: anthropologists classified Asian Indians not as ‘Mongolians,’ but as ‘Caucasians.’”³⁰ Thind, who applied and was granted citizenship by the United States District Court for the District of Oregon, argued that despite the fact he was not pale in complexion he was racially “‘Caucasian,’ therefore ‘white,’ and therefore eligible for citizenship.”³¹ The Bureau of Naturalization appealed the District Court’s decision granting Thind citizenship, and the case was subsequently certified to the Supreme Court.³²

In Thind, also authored by Justice Sutherland, the Court ruled unanimously against Thind.³³ The Justices acknowledged his argument but asserted:

[T]he words “free white persons” are words of common speech, to be interpreted in accordance with the understanding of the common man, synonymous with the word “Caucasian” only as that word is popularly understood … it does not include the body of people to whom the appellee belongs. It is a matter of familiar observation and knowledge that the physical group characteristics of the Hindus render them readily distinguishable from the various groups of persons in this country commonly recognized as white.³⁴

The decision directly contradicted the precedent set months earlier in Ozawa. Unlike Ozawa, Thind was able to prove he was Caucasian “under the science of the time,” yet was still denied citizenship.³⁵ Later in the opinion, the Court hinted that the true rationale for the discrepancy lay in how easily “children of English, French, German, Italian, Scandinavian, and other European parentage” could assimilate, compared to “the children born in this country of Hindu parents [who] would retain indefinitely the clear evidence of their ancestry.”³⁶

The Thind decision made it impossible for Asian Indians to gain citizenship under the Naturalization Act of 1906 which required eligible applicants be “free white persons.”³⁷ Furthermore, the decision disregarded both precedent and scientific classifications, favoring instead the approach of “familiar observation and knowledge.”³⁸ The abrupt reversal between Ozawa and Thind was not only jarring, but raised another question: should citizenship be treated as a concrete legal construct, or as a malleable concept that can shift to align with prevailing social and political goals rather than consistent legal principles?

C. Modern Tensions in Birthright Citizenship

A century later, the same tension between legal rights and social goals reemerges, this time, in debates over birthright citizenship. In Barbara v. Trump, the question is no longer whether someone is “white” enough to naturalize, but whether the government can narrow who is “American” enough to be recognized as a citizen by birth.³⁹ The through line from Ozawa and Thind to Barbara is not race itself, but the government’s recurring impulse to redefine citizenship in ways that exclude certain groups under the guise of legal interpretation.

On January 20, 2025, President Donald Trump issued Executive Order 14160, Protecting the Meaning and Value of American Citizenship.⁴⁰ The Executive Order is “aimed at ending birthright citizenship for children of undocumented immigrants and those with lawful but temporary status in the United States.”⁴¹ The Executive Order claims that the Fourteenth Amendment was never meant to include birthright citizenship of individuals born in the United States but not “subject to the jurisdiction thereof.”⁴² This category of individuals supposedly includes: (1) children born to an undocumented mother and a father who is neither a citizen nor a lawful permanent resident at the time of birth; and (2) children born to a mother who is a temporary visitor and a father who is neither a citizen nor a lawful permanent resident.⁴³ The order directed government agencies in the United States to stop issuing documents recognizing children under these categories as United States citizens beginning February 19th, 2025.⁴⁴

In Barbara v. Trump, decided on July 10, 2025, “[a] federal court in New Hampshire blocked President Trump’s executive order restricting birthright citizenship and certified a nationwide class that protects the citizenship rights of all children born on U.S. soil.”⁴⁵ Among other holdings, Judge Joseph Laplante concluded that the denial of citizenship status to newborns, even temporarily, constitutes irreparable harm and that the phrase “subject to the jurisdiction thereof” in the Fourteenth Amendment does not involve considerations of domicile or immigration status.⁴⁶

On September 26th, 2025, the Trump administration asked the Supreme Court to review the Barbara decision, along with another relevant ruling from the Ninth Circuit.⁴⁷ Given the significance of the constitutional issue, legal scholars widely anticipate that the Supreme Court will grant review and hear the case.⁴⁸ The impending arguments set the stage for a broader discussion on how the legal understanding of citizenship has evolved up until this point and how past decisions should or should not inform the Supreme Court moving forward.

III. DISCUSSION

The Ozawa and Thind decisions show that race, more specifically Whiteness, is a construct that can be redefined by the law in order to exclude unwanted persons and preserve an idea of citizenship as a privilege reserved for the racially and culturally acceptable. Today, the implications of Barbara v. Trump will force the Supreme Court to confront this issue once again.⁴⁹ The question is no longer framed in the blunt racial terms of Ozawa or Thind, but the underlying theme is familiar: whether the government can legally narrow who counts as “American” by redefining eligibility for citizenship. The outcome will determine not just the fate of the children directly affected by the executive order, but also whether the United States remains faithful to its constitutional promise that citizenship is a right of birth, not a privilege contingent on presidential or judicial interpretation.

A. The Instability of Citizenship as a Legal Construct

The right of citizenship, as established by the Fourteenth Amendment, was meant to be a fixed constitutional guarantee—not a political variable. As one source notes, “the aim of the Amendment was to eliminate the existence of a class of people who were subjected to American law but excluded from American legal rights.”⁵⁰ This principle established citizenship as a constitutional constant, not a privilege to be granted or withdrawn at will.

Yet, history demonstrates that its meaning has repeatedly shifted with social and political winds. When the government alters who “belongs,” it destabilizes not only the lives of those excluded but also public confidence in the rule of law itself. For example, in the aftermath of Thind at least sixty-five Asian Indians were stripped of their citizenship between 1923 and 1927.⁵¹ One former citizen even committed suicide following his denaturalization.⁵² The effects of a malleable definition of citizenship can be devastating. The Supreme Court’s review of Barbara v. Trump presents a pivotal opportunity to remember the original goals the Fourteenth Amendment and reaffirm the Amendment’s core promise: that the right to belong in one’s own country cannot depend on shifting politics or executive discretion.

B. Lessons from History for the Court’s Review

Ozawa and Thind demonstrate the dangers of allowing social prejudice and shifting political goals to shape legal definitions of who belongs. In both cases, the Court’s definition of race—first through scientific classifications, then through “common knowledge”—resulted in arbitrary and exclusionary outcomes that undermined the rule of law and perpetuated inequality, In reviewing Barbara v. Trump, the Supreme Court, must resist the temptation to allow the political and social goals of the President to distort the Constitution’s plain text. Birthright citizenship under the Fourteenth Amendment is clear: all persons born in the United States, subject to its jurisdiction, are citizens.

The Court should anchor its interpretation firmly in Wong Kim Ark, reaffirming that citizenship by birth is a fixed constitutional guarantee, not a negotiable privilege subject to political whims or social convenience. In a particularly telling passage from the case, the Court asked how citizenship could be denied to the children of Chinese immigrants when it extended to the children of Scottish, German, and other immigrants.⁵³ This observation not only highlighted the notion that United States citizenship was not racially restricted, but also established that even though Congress had barred Chinese immigrants themselves from naturalization, a law not repealed until 1943, their children remained “subject to the jurisdiction” of the United States and therefore qualified for citizenship at birth. Moreover, a narrow reading of the Citizenship Clause would destabilize established precedent and create a subclass of stateless persons born in the U.S, effectively undermining the original aim of the Fourteenth Amendment. Anchoring the Court’s review in this precedent would ensure that the United States honors both the letter and the spirit of the Fourteenth Amendment while protecting individuals from arbitrary exclusion.

IV. CONCLUSION

The evolution from Ozawa and Thind to Barbara v. Trump exemplify how the boundaries of citizenship remain a contested space between inclusion and exclusion. While the vocabulary has shifted from race to birthright, the underlying struggle over who counts as American persists. The Supreme Court now faces a choice similar to that of a century ago: whether to reaffirm a truly inclusive vision of citizenship rooted in the Fourteenth Amendment, or to allow political fears to narrow it once again. The lesson of Ozawa and Thind is clear: when courts permit social constructs to define legal rights, equality and belonging become negotiable. Barbara v. Trump presents an opportunity to correct that historical pattern and reaffirm that citizenship by birth is a fixed, non-negotiable constitutional guarantee.

Cover Photo by David Trinks on Unsplash

Mofetoluwa Koya

References

1
169 U.S. 649 (1898).
2
260 U.S. 178 (1922).
3
261 U.S. 204 (1923).
4
U.S. Const., amend. XIV.
5
United States v. Wong Kim Ark, 169 U.S. 649, 652 (1898).
6
United States v. Wong Kim Ark (1898), Nat’l Const. Ctr., https://constitutioncenter.org/the-constitution/supreme-court-case-library/united-states-v-wong-kim-ark-1898[https://perma.cc/Q76J-X3X7] (last visited Oct. 13, 2025).
7
Id.
8
Wong Kim Ark’s Legacy Lives On With Us, Asian L. Caucus (Jan. 20, 2025), https://www.asianlawcaucus.org/news-resources/news/wong-kim-arks-legacy-birthright-citizenship[https://perma.cc/W8WK-SNFA].
9
Wong Kim Ark, 169 U.S. at 653.
10
Wong Kim Ark, 169 U.S. at 705; Nat’l Const. Ctr., supra note 6.
11
Birthright Citizenship in the United States, Am. Immigr. Council, (Mar. 14, 2025), https://www.americanimmigrationcouncil.org/fact-sheet/birthright-citizenship-united-states/ [https://perma.cc/M37T-TR5G].
12
Ozawa v. United States, 260 U.S. 178, 189 (1922).
13
Ozawa v. United States (1922), Immigr. Hist., https://immigrationhistory.org/item/takao-ozawa-v-united-states-1922/[https://perma.cc/FWE2-SGSY].
14
Ozawa, 260 U.S. at 189.
15
Id.
16
Ozawa v. United States (1922), supra note 13.
17
Ian Haney-Lopez, White by Law 57 (1996).
18
Ozawa, 260 U.S. at 192.
19
Daksha Pillai, United States v. Bhagat Singh Thind: Dual Legacies of a Forgotten Supreme Court Case, The Gilder Lehrman Inst. of Am. Hist., https://www.gilderlehrman.org/sites/default/files/file_media/38_Pillai.pdf [https://perma.cc/EE4E-NSAM]; Haney-Lopez, supra note 16, at 57.
20
Haney-Lopez, supra note 17. at 57.
21
Ozawa, 260 U.S. at 197.
22
Id.
23
John Fiero, Ozawa v. United States, EBSCO: Research Starters (2023), https://www.ebsco.com/research-starters/history/ozawa-v-united-states, [https://perma.cc/8QS9-94VY].
24
Haney-Lopez, supra note 17, at 60.
25
Id.
26
Id.
27
United States v. Thind, 261 U.S. 204, 206 (1923).
28
Haney-Lopez, supra note 17, at 61.
29
Id.
30
Id.
31
Pillai, supra note 19; Haney-Lopez, supra note 17, at 6.
32
Pillai, supra note 19.
33
Id.
34
Thind, 261 U.S. at 215.
35
Pillai, supra note 19.
36
Thind, 261 U.S. at 215.
37
Pillai, supra note 19.
38
Haney-Lopez, supra note 17, at 64.
39
Barbara v. Trump, No. 25-cv-244-JL-AJ, 2025 U.S. Dist. LEXIS 130805 at *1, *4, (D.N.H. Jul. 10, 2025).
40
U.S. Citizenship & Immigr. Servs., IP-2025-0001, USCIS Implementation Plan of Executive Order 14160 – Protecting the Meaning and Value of American Citizenship (2025).
41
Birthright Citizenship in the United States, supra note 11.
42
Exec. Order No. 14160, 90 Fed. Reg. 12345 (Jan. 20, 2025).
43
U.S. Citizenship & Immigr. Servs., supra note 40.
44
Id.; Barbara v. Trump, 2025 U.S. Dist. LEXIS 130805, at *1.
45
Barbara v. Trump, 2025 U.S. Dist. LEXIS 130805, at *1; Federal Court Blocks Trump Birthright Citizenship Order, Certifies Nationwide Class Protecting All Impacted Babies, ACLU, (July, 10, 2025 11:00 am), https://www.aclu.org/press-releases/federal-court-blocks-trump-birthright-citizenship-order-certifies-nationwide-class-protecting-all-impacted-babies[https://perma.cc/8CJB-CSTP].
46
Barbara v. Trump, 2025 U.S. Dist. LEXIS 130805, at *38, *18.
47
Washington v. Trump, 145 F.4th 1013, 1019, (9th Cir. 2025) (holding that the executive order “is invalid because it contradicts the plain language of the Fourteenth Amendment’s grant of citizenship to ‘all persons born in the United States and subject to the jurisdiction thereof.’”).
48
Erwin Chemerinsky, The Trump docket, SCOTUSBlog (Oct. 7, 2025), https://www.scotusblog.com/2025/10/the-trump-docket/[https://perma.cc/BS3V-YVQF].
49
Barbara v. Trump, 2025 U.S. Dist. LEXIS 130805, at *1.
50
Birthright Citizenship in the United States, supra note 11.
51
Haney-Lopez, supra note 17, at 64.
52
Id.
53
United States v. Wong Kim Ark, 169 U.S. 649, 667 (1898).