February 7, 1973
Senate Select Committee on Presidential Campaign Activities is established. Senator Sam Ervin (D-NC) is its chairman.

March 21, 1973
John Dean tells President Nixon, “We have a cancer – within – close to the Presidency, that’s growing.” He tells the president that the burglars are demanding money and that maybe one million dollars would be needed in the end. “We could get that…,” the president replies.

March 23, 1973
Prior to Judge John Sirica imposing sentences on the convicted burglars, James McCord writes a letter to the judge claiming pressure had been applied to the defendants to ensure silence. Perjury was committed in the courtroom. Sirica makes the letter public and imposes harsh sentences, ranging from twenty to forty years, to force the defendants’ cooperation.

April 6, 1973
John Dean begins cooperating with Watergate prosecutors.

April 17, 1973
White House staff will appear before the Senate committee, says Nixon, who promises major new developments. An official White House statement claims Nixon had no prior knowledge of the break-in.

April 22, 1973
Nixon sends Dean to Camp David to write a report about Watergate.

April 30, 1973
Appearing on national television, Nixon announces the dismissal of Dean and the resignations of his closest advisors, Haldeman and Ehrlichman. Attorney General Kleindienst also resigns. Elliot Richardson is appointed to replace him.

May 3, 1973
According to a Louis Harris poll following the resignations of his key assistants, 54% believes the president’s credibility has suffered, rendering him less effective, yet only 42% agree that he “does not inspire confidence personally….” A strong majority believe “his own office was deeply involved in the Watergate affair,” and almost as many (51%) believe his action “has gone a long way toward restoring public confidence in the integrity of the White House.” Most are willing to give the president the benefit of the doubt, believing that Democrats as well as Republicans engage in dirty politics.

May 4, 1973
President Nixon appoints General Alexander Haig to replace Haldeman as White House chief of staff.

May 18, 1973
Having begun its work a day earlier, the Senate Watergate committee now begins televised hearings. Richardson announces former solicitor general Archibald Cox as the Justice Department’s special prosecutor.

June 3, 1973
The Post reports that John Dean has told investigators that he discussed the cover-up with Nixon at least 35 times.

June 13, 1973
Prosecutors find a memo to Ehrlichman containing detailed plans to burglarize the office of Dr. Lewis Fielding, Daniel Ellsberg’s psychiatrist.

June 25, 1973
Dean testifies before the Senate Watergate committee claiming Nixon was involved in the cover-up soon after the break-in and that the White House had conducted political espionage for years.

July 7, 1973
Claiming executive privilege, Nixon refuses to grant the Senate Watergate committee access to presidential documents. He informs Senator Ervin that he will not testify before the committee.

July 16, 1973
Alexander Butterfield, a former aide to the president and one of the few who knew about Nixon's tape recorders, testifies before the Senate committee and says that “there is tape in the Oval Office.” In doing so, he supposed he was confirming what Haldeman had already told the committee. This sets off a legal battle between the White House, special prosecutor’s office, Judge Sirica, and the Watergate committee.

July 18, 1973
Nixon orders an end to secret taping.