Dash became famous for his televised interrogations during the hearings held by the United States Congress on the Watergate incident.

[3] He interrupted his studies when at the age of 18, with the United States engaged in fighting World War II, Dash enlisted in the Army Air Corps and served as a bombardier navigator, flying missions over Italy.

Dash became a law professor at Georgetown University, where he was working when he was asked to help United States Senator Sam Ervin, head of the Senate Committee charged to investigate the possible involvement of President Richard Nixon in the burglary of offices used by the Democratic Party at the Watergate Hotel in Washington, D.C., and the effort to obstruct investigation of the burglary.

After working for the investigation for four years, Dash resigned to protest Starr's appearance before the United States House Committee on the Judiciary.

Dash died in Washington, D.C., of congestive heart failure, aged 79, on the same day as Archibald Cox, the special prosecutor for the Watergate scandal.