Twenty-second Amendment to the United States Constitution
As worded, the primary focus of the 22nd Amendment is on limiting individuals twice elected to the presidency from being elected again. Due to this, several issues could be raised regarding the amendment's meaning and application, especially in relation to the 12th Amendment, ratified in 1804, which states, "But no person constitutionally ineligible to the office of President shall be eligible to that of Vice-President of the United States". While it is clear that under the 12th Amendment the original constitutional qualifications of age, citizenship, and residency apply to both the president and vice president, it is unclear whether someone who is ineligible to be elected president could be elected vice president. Because of this apparent ambiguity, there may be a loophole in the 22nd Amendment whereby a two-term former-president could be elected vice president and then succeed to the presidency as a result of the incumbent's death, resignation, or removal from office (or even succeed to the presidency from some other stated office in the presidential line of succession).
Twentieth Amendment to the United States Constitution
Section 3 further refines the earlier mentioned Twelfth Amendment provision by declaring that if the president-elect dies before Inauguration Day, the vice president-elect will be sworn in as president on that day and serve for the full four-year term to which that person was elected; it further states that if on Inauguration Day a president-elect has not yet been chosen, or if the president-elect fails to qualify, the vice president-elect would become Acting President on Inauguration Day until a president-elect is chosen or the president-elect qualifies. Section 3 also authorizes Congress to determine who should be acting president if a new president and vice president have not been chosen by Inauguration Day. Acting on this authority, Congress added "failure to qualify" as a possible condition for presidential succession in the Presidential Succession Act of 1947. Previously silent on this point, the lack of guidance nearly caused a constitutional crisis on a couple of occasions: when the House of Representatives seemed unable to break the deadlocked election of 1800 and when Congress seemed unable to resolve the disputed 1876 election.