The concept of denaturalization—stripping a naturalized citizen of their U.S. citizenship—has a long, politically charged, and constitutionally complex history in the United States. While now a rare and highly scrutinized legal process, denaturalization was once wielded more broadly as a tool of social and political control. Understanding this evolution sheds light on current debates and anxieties around citizenship, immigration, and civil liberties.

The Early Framework: Fraud and Behavior

Denaturalization formally entered federal law with the Naturalization Act of 1906, which was part of a broader effort to centralize and standardize immigration and citizenship rules. Though the law was primarily intended to reverse fraud during the naturalization process, it quickly became a tool to remove citizens deemed "un-American" based on their political beliefs, race, or behavior after naturalization.

As historian Patrick Weil describes in The Sovereign Citizen, this early period saw denaturalization applied most often to foreign-born citizens living abroad or affiliated with controversial ideologies. In practice, this process allowed the government to revoke citizenship from individuals for being Communists, Socialists, pacifists, or even for simply residing outside the country. Weil calls this a "cleansing" of the body politic—rooting out those deemed morally or ideologically unfit for American citizenship.

Expansion During World War II

The 1940 Nationality Act marked a significant expansion in the use of denaturalization, especially during wartime. The Justice Department ramped up its efforts to identify and strip citizenship from individuals thought to pose national security risks. Importantly, this law extended denaturalization power to include some native-born citizens as well, such as those who evaded the draft or served in foreign militaries.

At the time, the Supreme Court largely upheld these aggressive uses of denaturalization, citing the government's broad authority over foreign affairs. But cracks began to show in this legal foundation in the years that followed.

A Constitutional Turning Point: Afroyim v. Rusk

In 1967, the Supreme Court issued a landmark ruling in Afroyim v. Rusk that dramatically limited the government's ability to revoke citizenship. Justice Hugo Black, writing for the majority, concluded that citizenship is a constitutional right under the Fourteenth Amendment, and cannot be taken away by the government without the citizen's consent. “The very nature of our free government,” Black wrote, “makes it completely incongruous to have a rule of law under which a group of citizens temporarily in office can deprive another group of citizens of their citizenship.”

This ruling effectively ended the era of politically motivated denaturalizations and redefined American citizenship as an inviolable legal status, not a conditional privilege.

The Modern Grounds for Denaturalization

Since Afroyim, denaturalization has been used only under very narrow circumstances. As Weil and other legal scholars explain, there are two main grounds on which the U.S. government can revoke naturalization today:

1. Human rights violations – Most notably, this applies to individuals who concealed involvement in Nazi atrocities or other acts of genocide.
2. Fraud or misrepresentation during naturalization – The government must prove, by clear, convincing, and unequivocal evidence, that the individual was not legally eligible for citizenship due to material misrepresentations during the naturalization process.

In civil cases, the burden of proof is high, though not as strict as in criminal prosecutions. And while criminal denaturalization does require a “beyond a reasonable doubt” standard, civil proceedings do not require the government to provide the defendant with legal counsel, raising constitutional concerns for due process.

The Trump Era and Renewed Focus

Denaturalization surged back into the national conversation during Donald Trump's presidency. Building on an Obama-era program called Operation Janus, Trump's administration aggressively pursued denaturalization, creating a dedicated Denaturalization Section within the Department of Justice in 2020. This office focused on identifying naturalized citizens allegedly involved in war crimes, terrorism, or naturalization fraud.

Critics, including the National Association of Criminal Defense Lawyers, noted that the Trump Administration's use of civil denaturalization proceedings—where the accused has no guaranteed right to an attorney—raised due process concerns and threatened to chill the naturalization process for lawful permanent residents. They also warned of vague standards and a dangerously broad interpretation of “undesirable conduct.”

In 2021, President Joe Biden issued an executive order directing agencies to review denaturalization practices to ensure they were not being abused. However, with Trump now back in office, the Justice Department has again listed denaturalization as a “priority initiative.”

A June 2025 DOJ memo instructed attorneys to "maximally pursue denaturalization proceedings" against individuals who have committed crimes, engaged in fraud, or pose national security risks. Assistant Attorney General Brett Shumate emphasized that the civil nature of these proceedings allows the government more flexibility to act swiftly—prompting backlash from civil rights advocates who worry about abuses of power.

Final Thoughts

The evolution of denaturalization reflects deeper tensions about the meaning of American citizenship—whether it is a contract, a privilege, or an unalienable right. From its early use as a political tool to today's targeted enforcement mechanisms, denaturalization remains one of the most serious actions the government can take against a citizen.

At the Law Office of Steve Lopez, we believe that every individual facing immigration-related proceedings—whether removal, naturalization, or denaturalization—deserves strong, principled legal representation. If you or a loved one is facing a citizenship-related challenge, contact us today to discuss your legal rights.