Scott Armstrong was one of the lead investigators on the United States Senate Watergate Committee — and one of the four people in the room when Alexander Butterfield revealed the existence of Nixon’s secret Oval Office taping system. In this episode, Armstrong walks us through that pivotal moment in American history, how a single document raised suspicions, and what it was like to work behind the scenes on the most consequential political scandal of the 20th century.

We also discuss Armstrong’s early career at The Washington Post, his work with Bob Woodward on The Final Days and The Brethren, and his founding of the National Security Archive, which continues to fight for government transparency to this day.