The Twentieth Amendment, ratified in 1933, declares: "The terms of the President and Vice-President shall end at noon on the 20th day of January." It's worth noting that it doesn't say "and then their successors shall be sworn in;" that's just a logical inference. In other words, the Constitution specifies that Bush leaves office tomorrow, but not that Obama checks in. But since we're at all times supposed to have a President, somebody better be there to ask Obama to put his hand on a Bible!
Exactly fifty years after the birth of the Twentieth Amendment, Public Law 98-144 added Dr. Martin Luther King, Jr.'s birthday to the list of federal holidays. Well, not necessarily his actual birthday, January 15th, but rather the third Monday in January. Those two dates, the 15th and the third Monday of the first month, coincide any year New Year's Day is on a Monday. That happened just two years ago.
What I really wanted to know, however, is how often do the Twentieth Amendment and Public Law 98-144 align? This year of course, the inauguration comes one day after the King birthday holiday, but since it was recognized in 1983, have the two days coincided?
Yes, they have, once. That was for Bill Clinton's second inauguration, in 1997. Courtesy of timeanddate.com, I decided to look it up and see how often this phenomenon happens.
The answer is: not often. Inauguration Day will land on the third Monday of January next in 2025. After that, the two days match in 2053, 2081, and 2121.
I can hardly wait!