Tapes revealed that President Richard Nixon and his top advisers were involved in covering up a break-in at a Democratic National Committee office in the Watergate complex in Washington, D.C. Nixon resigned before he could be impeached, becoming the first president to step down. Several of his top advisers – including the White House lawyer, chief of staff and attorney general – did prison time. Nominated by: Barbara A. Perry, Director of Presidential Studies and Co-Chair of the Presidential Oral History Program at the University of Virginia’s Miller Center.