What does the U.S. Constitution say about what happens if a president dies or is removed from office?
Article II, Section 1 provides:
In case of the removal of the President from Office, or of his Death, Resignation, or Inability to discharge the Powers and Duties of said office, the Same shall devolve to the Vice President, and the Congress may by law provide for the case of removal, death, resignation or inability, both of the President and Vice President, declaring what officer shall then act as President, and such officer shall act accordingly, until the disability be removed, or a President shall be elected.
The Twelfth Amendment, added to the Constitution in 1804, says that should the president die, “the Vice President shall act as President.”
The question became whether Tyler should simply act as president until a new president was elected or chosen by Congress, or whether he would become the new president. Tyler acted swiftly and definitively, declaring that he should assume the presidency.