4. Watergate

­Watergate is the name of the scandal that caused Richard Nixon to become the only U.S. president to resign from office.

On May 27, 1972, concerned that Nixon's bid for reelection was in jeopardy, former CIA agent E. Howard Hunt, Jr., former New York assistant district attorney G. Gordon Liddy, former CIA operative James W. McCord, Jr., and six other men broke into the Democratic headquarters in the Watergate Hotel in Washington, D.C. They wiretapped phones, stole some documents, and photographed others.

When they broke in again on June 17 to fix a bug that wasn't working, a suspicious security guard called the Washington police, who arrested McCord and four other burglars. A cover-up began to destroy incriminating evidence, obstruct investigations, and halt any spread of scandal that might lead to the president. On August 29, Nixon announced that the break-in had been investigated and that no one in the White House was involved.

Despite his efforts to hide his involvement, Nixon was done in by his own tape recordings, one of which revealed that he had authorized hush money paid to Hunt. To avoid impeachment, Nixon resigned on August 9, 1974. His successor, President Gerald Ford, granted him a blanket pardon on September 8, 1974, eliminating any possibility that Nixon would be indicted and tried.

Washington Post reporters Bob Woodward and Carl Bernstein helped expose the scandal using information leaked by someone identified as Deep Throat, a source whose identity was kept hidden until 2005, when it was revealed that Deep Throat was former Nixon administration member William Mark Felt.

Learn about more political scandals in the next section, including the Iran-Contra Affair.