Video: Sen. Howard Baker asked: What did Nixon know and when did he know it?

Sen. Howard Baker, the leading Republican on the committee investigating the Watergate scandal surrounding President Nixon, asked the seminal question at the hearings: “What did the president know and when did he know it?”

Above is a clip of Baker speaking at the hearings in June 1973.

Baker has died, Senate Minority Leader Mitch McConnell announced Thursday on the Senate floor.