On January 20, in accordance with the Twentieth Amendment to the Constitution, Donald Trump officially assumed office as the President of the United States. This amendment mandates that the terms of the outgoing President and Vice President conclude at noon on that day, with their successors immediately commencing their terms.
The Twentieth Amendment, ratified on January 23, 1933, brought about the change of Inauguration Day from March 4 to January 20. This adjustment aimed to reduce the 'lame duck' period between the election and the beginning of a new president's term.
In 1985, President Reagan's second term began at noon on January 20. However, due to the date falling on a Sunday, public festivities were postponed to the following day, as noted by the Reagan presidential library.
A similar situation occurred in 2013 during President Barack Obama's second term. He took the oath of office in the Blue Room of the White House on Sunday, January 20, and then repeated the oath the next day during a public ceremony at the Capitol.
