Jerry Landay, reporting for ABC News.

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The incident happened on a Saturday night and became known as the "Saturday Night Massacre."

Nixon then had acting Attorney General Robert Bork dismiss Cox, and the president eliminated the office of special prosecutor. He gave the Justice Department the responsibility of continuing the investigation.

President Nixon had another political problem, in addition to Watergate. In late nineteen seventy-three, his vice president, Spiro Agnew, was forced to resign. A court had found Agnew guilty of violating tax laws.

President Nixon asked Gerald Ford to become the new vice president. Ford was a longtime member of Congress from Michigan.

By that time, some members of Congress were talking about trying to remove Nixon from office. Was the president covering up important evidence in the Watergate case? Was he, in fact, guilty of crimes?

In April nineteen seventy-four, Nixon surrendered some of the recordings of conversations in his office. However, three important ones were missing. The Nixon administration tried to explain, saying the tape machine had failed to record two of those conversations. The third recording, it said, had been erased accidentally. This became known as the famous "eighteen-minute gap."

Many Americans did not believe these explanations.

Two months later, the Supreme Court ruled that a president cannot hold back evidence in a criminal case. It said there is no presidential right of privacy in such a case.