“We are definitely taking advantage of the fact that most senior-level people in Washington depend on a lot of young associates and subordinates to get anything done,” said Rep. Jamie Raskin (D-Md.), a member of the select committee. “A lot of these people still have their ethics intact and don’t want to squander the rest of their careers for other people’s mistakes and corruption.”

Aides like Cassidy Hutchinson, a close adviser to former Trump chief of staff Mark Meadows, and Ken Klukowski, who advised former Justice Department official Jeffrey Clark, have helped the select committee fill in gaps about Trump’s private meetings, calls and efforts to overturn the 2020 election that investigators could otherwise only obtain from the principal players themselves.

These interviews have given committee members confidence that they’ll be able to tell the full story of Trump’s attempt to stop the transition of power — even though central figures like Clark, Meadows, outside adviser Steve Bannon and attorney John Eastman have declined to provide substantive testimony.