When did the White House tapes that incriminated Nixon first surface? Which committee (committee members) first listened to them?
5 minutes and 52 seconds into the video this journalist(Chris Ruddy) says that “when Watergate started, nobody had even heard of the Watergate tapes”. Nobody?
Trump ally warns of ‘mortal threat’ to his presidency
It was a big deal. Up to that point, all of the evidence had been based on testimony. The conflicts made it clear somebody was lying but there was no way to establish who was testifying truthfully. The tapes suddenly opened the possibility of having objective evidence. So the whole focus of the investigation shifted to being about getting access to the tapes (or, from the other side, denying access to the tapes).
And interestingly, Nixon’s lawyers argued that he should be allowed to keep this evidence hidden, and ignore subpoenas. This is the exact argument that Trump’s lawyers are using today.
In fact, they are arguing that the unanimous decision, United States v. Nixon, 418 U.S. 683 (1974) (ordering release of the tapes) was a wrong decision by the supreme court of the day, and would not happen today, therefore, President Trump should be allowed to ignore subpoenas or instruct others to ignore subpoenas.
On August 5 Nixon turned over the “smoking gun” tape to Department of Justice Special Prosecutor Leon Jaworski, who surrendered them to the House Judiciary Committee.
At that point ten members of the Committee who previously had supported Nixon, publicly announced they would vote for impeachment. They were joined by the House Republican leader, John Rhodes. On August 7 a delegation of Republican Senators told Nixon the Senate would vote to convict him, and the next night, Nixon announced he would resign.
While Nixon vs. The United States was unanimous, it was an 8-0 vote. Rehnquist sat out due to ties to the Nixon administration. So don’t make the mistake of thinking it was a 9-0 decision.
Outside people were listening to some of the tapes much earlier than July 1974. E.g., the infamous 18 1/2 gap tape was being examined by November of 1973. (This tape was made 3 days after the break in. Forensic analysis proved that there were at least 5 separate erasures made by hand. So the Rosemary Woods story was debunked and she was lying.)