Twentieth Amendment to the United States Constitution
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The Twentieth Amendment (Amendment XX) to the United States Constitution moved the beginning and ending of the terms of the president and vice president from March 4 to January 20, and of members of Congress from March 4 to January 3. It also has provisions that determine what is to be done when there is no president-elect. The Twentieth Amendment was adopted on January 23, 1933. The amendment reduced the presidential transition and the "lame duck" period, by which members of Congress and the president serve the remainder of their terms after an election. The amendment established congressional terms to begin before presidential terms and that the incoming Congress, rather than the outgoing one, would hold a contingent election if the Electoral College deadlocked regarding either the presidential or vice presidential elections.