Article I, Section 8, Clause 4:
[The Congress shall have Power . . .] To establish an uniform Rule of Naturalization, and uniform Laws on the subject of Bankruptcies throughout the United States; . . .
Although, as has been noted, throughout most of our history there were significant racial and ethnic limitations upon eligibility for naturalization, the present law prohibits any such discrimination.
The right of a person to become a naturalized citizen of the United States shall not be denied or abridged because of race or sex or because such person is married. 1 However, any person
who advocates or teaches, or who is a member of or affiliated with any organization that advocates or teaches . . . opposition to all organized government, or
who advocates or teaches or who is a member of or affiliated with any organization that advocates or teaches the overthrow by force or violence or other unconstitutional means of the Government of the United States or who is a member of or affiliated with the Communist Party, or other communist organizations, or other totalitarian organizations is ineligible. 2 These provisions moreover are
applicable to any applicant for naturalization who at any time within a period of ten years immediately preceding the filing of the petition for naturalization or after such filing and before taking the final oath of citizenship is, or has been found to be, within any of the classes enumerated within this section, notwithstanding that at the time the petition is filed he may not be included within such classes. 3
Other limitations on eligibility are also imposed. Eligibility may turn upon the decision of the responsible officials whether the petitioner is of
good moral character. 4 The immigration and nationality laws themselves include a number of specific congressional determinations that certain persons do not possess
good moral character, including persons who are
habitual drunkards, 5 adulterers, 6 polygamists or advocates of polygamy, 7 gamblers, 8 convicted felons, 9 and homosexuals. 10 In order to petition for naturalization, an alien must have been resident for at least five years and to have possessed
good moral character for all of that period.
The process of naturalization culminates in the taking in open court of an oath
(1) to support the Constitution of the United States; (2) to renounce and abjure absolutely and entirely all allegiance and fidelity to any foreign prince, potentate, state, or sovereignty of whom or which the petitioner was before a subject or citizen; (3) to support and defend the Constitution and the laws of the United States against all enemies, foreign and domestic; (4) to bear true faith and allegiance to the same; and (5) (A) to bear arms on behalf of the United States when required by the law, or (B) to perform noncombatant service in the Armed Forces of the United States when required by the law, or (C) to perform work of national importance under civilian direction when required by law. 11
Any naturalized person who takes this oath with mental reservations or conceals or misrepresents beliefs, affiliations, and conduct, which under the law disqualify one for naturalization, is subject, upon these facts being shown in a proceeding brought for the purpose, to have his certificate of naturalization cancelled. 12 Moreover, if within a year of his naturalization a person joins an organization or becomes in any way affiliated with one which was a disqualification for naturalization if he had been a member at the time, the fact is made prima facie evidence of his bad faith in taking the oath and grounds for instituting proceedings to revoke his admission to citizenship. 13