After Nixon’s 49-state victory in 1972, the atmosphere changed. In the wake of that landslide, Nixon demanded and accepted resignations at the White House and throughout the administration. The president planned a thorough reorganization of the federal government.

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On the Hill, Senator Mike Mansfield and his Democratic colleagues were not prepared to let the Watergate burglary and the “dirty tricks” of the 1972 campaign slide, despite Nixon’s formidable popularity. Mansfield obtained unanimous agreement to impanel a small investigative committee chaired by the respected Senator Sam Ervin.

At its inception in February 1973, the Senate Watergate Committee had only a June 1972 burglary and the well-publicized “dirty tricks” to investigate. However, soon after the committee’s creation, evidence began to emerge of a White House–orchestrated cover-up of the Watergate burglary.

As evidence implicating the White House mounted, the administration displayed no inclination toward negotiation or accommodation with the Senate Watergate Committee. On March 15, 1973, Nixon issued an edict asserting executive privilege, declaring that White House aides and papers were entirely off limits to the committee. If the committee desired to press the issue, the president said, it could pursue a contempt prosecution through the courts.

Pressed for his reaction, Ervin said Nixon’s position was “executive poppycock, akin to the divine right of kings.” Ervin declared that his committee had no intention of submitting to the suggested judicial delays, but would instead utilize the Senate’s sergeant at arms to arrest any recalcitrant White House aide, bring him to the bar of the Senate for trial, and ultimately compel him to testify.

As damaging revelations continued to mount and the stigma of cover-up gathered strength, the White House floated trial balloons, offering the Watergate Committee possible closed-door interviews with White House aides. Ervin continued to insist on public testimony, saying that “White House aides are not royalty or nobility who can be excused from testifying under oath and in public.”

By mid-April 1973, Nixon’s resistance to testimony by White House aides had collapsed, and a number of them testified. This testimony disclosed the White House taping system and confirmed the existence of tapes. Those disclosures ultimately led to Nixon’s departure from office.

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This performance of the Senate Watergate Committee stands as one example of effective congressional oversight. There have been others. The one essential ingredient has been the testimony, at public hearings, compelled if necessary, of witnesses able to give a firsthand account of matters of national importance. Televised hearings have proved to be the one effective way to focus the nation’s attention on questions of crucial significance.