Section 1 of Article Two of the United States Constitution sets forth the eligibility requirements for serving as president of the United States:
No person except a natural born Citizen, or a Citizen of the United States, at the time of the Adoption of this Constitution, shall be eligible to the Office of President; neither shall any Person be eligible to that Office who shall not have attained to the Age of thirty-five Years, and been fourteen Years a Resident within the United States.
The Twelfth Amendment states, “No person constitutionally ineligible to the office of President shall be eligible to that of Vice-President of the United States.” The Fourteenth Amendment does not use the phrase natural-born citizen. It does provide that “All 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.”
Black’s Law Dictionary (9th Edition) defines “Natural Born Citizen” as “A person born within the jurisdiction of a national government”.
The Constitution does not define the phrase natural-born citizen, and various opinions have been offered over time regarding its precise meaning. A 2011 Congressional Research Service report stated
The weight of legal and historical authority indicates that the term “natural born” citizen would mean a person who is entitled to U.S. citizenship “by birth” or “at birth”, either by being born “in” the United States and under its jurisdiction, even those born to alien parents; by being born abroad to U.S. citizen-parents; or by being born in other situations meeting legal requirements for U.S. citizenship “at birth”. Such term, however, would not include a person who was not a U.S. citizen by birth or at birth, and who was thus born an “alien” required to go through the legal process of “naturalization” to become a U.S. citizen.[1]