Acting President of the United States

There is an established presidential line of succession in which officials of the United States federal government may be called upon to be acting president if the incumbent president becomes incapacitated, dies, resigns, or is removed from office (by impeachment by the House of Representatives and subsequent conviction by the Senate) during their four-year term of office; or if a president-elect has not been chosen before Inauguration Day or has failed to qualify by that date.

Article II, Section 1, Clause 5 of the Constitution prescribes three eligibility requirements for the presidency.

[1] Article II, Section 1, Clause 6 makes the vice president first in the line of succession.

The precedent he set in 1841 was followed subsequently on seven occasions when an incumbent president died prior to the presidential succession being enshrined in the Constitution through section 1 of the Twenty-fifth Amendment.

Due to this lack of clarity, later vice presidents were hesitant to assert any role in cases of presidential inability.

[15] On two occasions, in particular, the operations of the executive branch were hampered due to the fact that there was no constitutional basis for declaring that the president was unable to function: Proposed by the 89th Congress and subsequently ratified by the states in 1967, the Twenty-fifth Amendment, as noted above, established formal procedures for addressing instances of presidential disability and succession.