President Nixon, right, discusses improving conditions at a California state park as John D. Ehrlichman, Nixon's domestic affairs adviser, listens in this 1972 photo. Ehrlichman was imprisoned for 18 months for his part in the Watergate conspiracy.

This picture, with Gerald Ford seated behind him, shows President Nixon delivering the State of the Union message in January 1974. The following August, Nixon would step down as the 37th president with a 2,026-day term, urging Americans to rally behind Ford. President Ford fully pardoned Nixon one month later.

President Richard Nixon pounds his fist on the podium as he answers a question during his televised appearance before questioners made up of members of the National Broadcasters Association in Houston, Texas, March 19, 1974. President Nixon declared that dragging out Watergate drags down America.

President Nixon gestures toward transcripts of White House tapes after announcing he would turn them over to House impeachment investigators and make them public in April of 1974.

The first and last pages of the complaint filed in federal court in Washington, D.C., by the Senate Watergate Committee, Aug. 9, 1973. The complaint names as defendant Richard M. Nixon, individually and as President of the United States. Their signatures appear on the last page of the complaint.

President Richard Nixon embraces his daughter, Mrs. Julie Eisenhower, Aug. 8, 1974, after informing his family of his decision to resign, in a photo released by the White House. The photo was made in the family's living quarters.

President Richard M. Nixon announces on Aug. 8, 1974, he will resign the office of President, effective noon Friday, Aug. 9, 1974, during a broadcast from the Oval Room of the White House.

Richard Nixon gives a thumbs up as he stands beside his wife Pat in the East Room of the White House Aug. 9, 1974, as he says farewell to the people who served him before his resignation. Tricia Nixon Cox, one of his daughters, is next to his wife. At left are David and Julie Eisenhower.

President Richard M. Nixon stands by his wife Pat Nixon in the East Room of the White House Aug. 9, 1974, where he made a farewell address to the members of the White House staff. The president boarded a helicopter immediately following his address for a short flight to nearby Andrews Air Force Base and a flight to California.

On the day of his resignation, Aug. 9, 1974, Richard M. Nixon waves goodbye from the steps of his helicopter as he leaves the White House following a farewell address to his staff. The Watergate scandal forced Nixon to become the first U.S. president to resign from office.

Richard Nixon says goodbye with a victorious salute to his staff members outside the White House as he boards a helicopter after resigning the presidency on Aug. 9, 1974. His resignation came after approval of an impeachment article against him by the House Judiciary Committee for withholding evidence from Congress.

President Gerald Ford signs a document granting former President Richard M. Nixon "a full, free and absolute pardon" for all "offenses against the United States" during the period of his presidency. Ford signed the document Sept. 8, 1974, in his White House office.