Answer:
Connection to and cover-up of the June 17, 1972 Watergate Building break-in, which is the Democratic National Committee's headquarters.
Step-by-step explanation:
After the June 17 failed break-in the trail and interrogation of the perpetrators and the information provided by William Mark and Judy Hoback led to an extensive investigation of Richard Nixon's involvement in the break-in and its subsequent cover-up.
Due to the investigation, Nixon and other Republican Party members were found to have direct involvement in the break-in.
The investigation, trial, pressure from the American people, and other factors forced President Nixon's resignation on the 9th of August, 1974, although he would then be pardoned by President Ford on September 8th, 1974.