Congress has established terms and conditions under which foreign-born persons may acquire citizenship through a process known as naturalization. In addition to providing a framework for the acquisition of citizenship for persons born abroad to U.S. citizen parents, federal law sets forth a process for a lawful permanent resident (LPR) to become a U.S. citizen if he or she meets certain statutory requirements. As discussed in another CRS product, most LPRs residing in the United States are eligible for naturalization. The process to revoke an individual's previously granted naturalization status is commonly known as denaturalization. This process may generally occur any time after naturalization has been granted, with few exceptions. Section 1451 of Title 8 of the U.S. Code specifies several grounds upon which to revoke naturalization. Following denaturalization, an individual's status reverts back to the status held before becoming a U.S. citizen. An individual may also face criminal penalties or imprisonment if a court determines that he or she "knowingly procure[d] or attempt[ed] to procure, contrary to law, the naturalization of any person."
The Trump Administration has issued multiple directives on denaturalization. On January 20, 2025, President Trump issued an executive order that, among other things, requires the Secretary of State, in coordination with the Attorney General, the Secretary of the Department of Homeland Security (DHS), and the Director of National Intelligence, to "ensure the devotion of adequate resources to identify and take appropriate action for offenses described in 8 U.S.C. § 1451." On June 11, 2025, the Assistant Attorney General for the Civil Division of the Department of Justice (DOJ) directed attorneys to prioritize denaturalization cases as a civil enforcement priority (June memo). Additionally, it has been reported that the Trump Administration issued internal guidance in December 2025 asking DHS's U.S. Citizenship and Immigration Services (USCIS) field offices to "supply [DOJ's] Office of Immigration Litigation with 100-200 denaturalization cases per month" for the remainder of FY2026, and the Administration has also reportedly expanded the types of DOJ attorneys handling denaturalization cases. The denaturalization process has been the subject of legislative interest in the 119th Congress, including both congressional hearings and legislative proposals (e.g., the SCAM Act (S. 3674 and H.R. 7156), the Naturalization Accountability Act (S. 4105), and the American Citizens First Act (S. 3318)).
This Legal Sidebar briefly explains the constitutional and statutory authorities for the denaturalization processes. The Sidebar then discusses recent executive branch denaturalization efforts.
Article I, Section 8 of the Constitution authorizes Congress "[t]o establish an uniform Rule of Naturalization." Pursuant to this authority, Congress enacted the Naturalization Act of 1790, which has since been amended several times. The last major amendments were enacted in the Immigration Act of 1990, which transferred responsibility for the naturalization process from the courts to the executive branch. (The 1990 Act originally delegated authority over this administrative naturalization process to the Attorney General, but it is now implemented by DHS.) In general, to naturalize under 8 U.S.C. § 1427, individuals must have resided continuously in the United States for five years as LPRs and must demonstrate that they have been and still are persons "of good moral character, attached to the principles of the Constitution of the United States, and well disposed to the good order and happiness of the United States" during the required period of residence. For more information about the naturalization process and a policy overview, see this CRS report.
Early naturalization laws did not include denaturalization provisions, and there was uncertainty over when or whether courts could set aside an earlier naturalization determination. President Theodore Roosevelt called on Congress to revise the existing naturalization laws, including to formalize denaturalization proceedings, following reports of widespread abuse. The first denaturalization law was included in the Naturalization Act of 1906 and delegated to U.S. Attorneys the authority, "upon affidavit showing good cause therefor, to institute proceedings . . . for the purpose of setting aside and canceling the certificate of citizenship on the ground of fraud" or illegal procurement. The Nationality Act of 1940 modeled the 1906 law and also included a more comprehensive set of rules to rescind citizenship from both naturalized and native-born U.S. citizens who commit certain acts "with the intention of relinquishing [U.S.] nationality" (also known as expatriation). The Immigration and Nationality Act of 1952 (INA) changed the basis to denaturalize an individual "from fraud and illegal procurement to procurement by concealment of material fact or by willful misrepresentation."
To begin the denaturalization process, DHS's USCIS recommends to the DOJ that it institute civil revocation or criminal prosecution proceedings against an identified individual. For civil revocation, a DOJ attorney files a complaint with an affidavit showing good cause in the judicial district where the naturalized citizen lives. The DOJ attorney can initiate these proceedings under the civil or criminal denaturalization statutes, depending on the facts presented in each case. Most cases are litigated as civil proceedings, where there is no statute of limitations or right to a court-appointed attorney, and the burden of proof is "clear, convincing, and unequivocal evidence which does not leave the issue in doubt." For criminal proceedings brought under 18 U.S.C. § 1425, there is generally a statute of limitations of 10 years, the burden of proof is beyond a reasonable doubt, and the individual has a right to counsel.
In civil denaturalization proceedings under 8 U.S.C. § 1451(a), individuals can have their naturalization status revoked if a court determines the certificate of naturalization and citizenship order were either "illegally procured or were procured by concealment of a material fact or by willful misrepresentation." The Supreme Court has held that to establish that an individual "illegally procured" naturalization under Section 1451(a), the government must prove that he or she failed "to comply with the statutory prerequisites for naturalization," as set forth in the INA. An example of this would be individuals who did not have the requisite good moral character leading up to and at the time they sought to naturalize.
To establish procurement by concealing a material fact or willful misrepresentation, according to the Supreme Court, the government must establish four independent requirements: (1) there must have been a misrepresented or concealed fact; (2) the misrepresentation or concealment must have been willful; (3) it must have been material; and (4) "the naturalized citizen must have procured citizenship as a result of the misrepresentation or concealment." The Supreme Court has determined that the test for whether the concealments or misrepresentations are material "is whether they have a natural tendency to influence the decisions of" DHS. To determine the natural tendencies, the Court explained "what is relevant is what would have ensued from official knowledge of the misrepresented fact . . . not what would have ensued from official knowledge of inconsistency between" the later-asserted truth and the earlier lie. An example of this would be an individual who intentionally lies at his or her naturalization interview to obtain citizenship. Although not codified in statute, the Supreme Court has held that the standard of proof for civil denaturalization is "clear, unequivocal, and convincing" evidence that does not leave "the issue in doubt." If the requisite burden is met, the court must enter an order revoking the naturalization order and canceling the naturalization certificate. Once the revocation process is complete, the individual's immigration status reverts back to the status held before naturalization.
An individual can also be denaturalized, within 10 years of naturalization, if convicted for criminal contempt for refusing to testify before a congressional committee on alleged "subversive activities." Further, if a naturalized citizen, within the first five years of naturalization, becomes a member of or is affiliated with an organization that is opposed to organized government or favors totalitarian forms of government, this is prima facie evidence that he or she "was not attached [at the time of naturalization] to the principles of the Constitution . . . and was not well disposed to the good order and happiness of the United States," which is required for naturalization under 8 U.S.C. § 1427(a), and a court may authorize denaturalization. Federal statute provides that family members who derived citizenship may also be denaturalized under these listed provisions.
As to criminal proceedings, under 18 U.S.C. § 1425(a), individuals who knowingly procure or attempt to procure naturalization of any person can be criminally prosecuted and, if found guilty, fined and/or imprisoned. After a conviction under Section 1425(a), the court in which the proceedings took place shall then issue an order revoking the individual's naturalization, under 8 U.S.C. § 1451(e). The Supreme Court held in 2017 that an individual violates Section 1425(a) only when he or she committed an illegal act that "played some role in [his or] her naturalization." The Court reminded that it has "never read a statute to strip citizenship from someone who met the legal criteria for acquiring it" and held that "qualification for citizenship is a complete defense to a prosecution brought under [Section 1425(a)]."
Other statutes addressing denaturalization include 8 U.S.C. §§ 1439(f) and 1440(c). Under these provisions, individuals can be denaturalized if they obtained naturalization through service in the U.S. military but later separated "under other than honorable conditions" before they served honorably for at least five years.
As mentioned earlier, once naturalization is revoked, an individual reverts back to his or her status before naturalization, which typically means LPR status. LPRs are subject to the grounds of deportability under immigration law (and, in certain cases, the grounds of inadmissibility if they are seeking to return to the United States from a trip abroad, including after a period of more than 180 days). According to DOJ's Journal of Federal Law and Practice, denaturalized individuals must surrender and deliver their naturalization certificates and any other documentation showing proof of U.S. citizenship (such as a U.S. passport), and DOJ notifies DHS and the State Department that the individual is no longer a U.S. citizen. Further, according to DOJ practice, "the government does not expend resources on civil denaturalization actions unless the ultimate goal is the removal of the [individual] from the United States" and DOJ "attorneys confirm that goal before filing the complaint."
Between 1968 and 2013, fewer than 150 individuals were denaturalized. The Obama Administration launched Operation Janus to investigate individuals who had orders of removal but later naturalized under different names. Operation Janus was expanded in 2019 during the first Trump Administration as Operation Second Look, which aimed to review an estimated 700,000 files.
The first Trump Administration also made a concerted effort to prioritize denaturalization. In 2017, Attorney General Sessions announced that the DOJ would aggressively pursue denaturalization. In 2018, USCIS announced that it intended to refer an additional 1,600 cases to the DOJ for denaturalization. In 2020, the DOJ's Civil Division created a section specifically dedicated to denaturalization cases. The goal of this new section was "to bring justice to terrorists, war criminals, sex offenders, and other fraudsters who illegally obtained naturalization." In 2021, President Biden issued an executive order that told agency heads to ensure that denaturalization policies and practices were "not used excessively or inappropriately." In 2022, the Biden Administration issued a new policy that certain nonprofit groups argued continued the first Trump Administration's denaturalization efforts. Between 2017 and 2025, it was reported that "over 130 cases were filed."
The Trump Administration has continued and expanded its efforts to prioritize denaturalization, Since the June 2025 memo was issued, the DOJ has pursued several civil denaturalization cases.