Video footage released by the January 6 committee shows Republican senator Josh Hawley running away from pro-Trump protesters just hours after he was pictured raising his fist in solidarity with them.
Democratic congresswoman Elaine Luria revealed the video at a prime-time hearing on Thursday after first showing a photograph of Mr Hawley showing his support to protesters before Congress met to certify the presidential election.
“As you can see in this photo, he raised his fist in solidarity with the protesters already amassing at the security gates,” she said.
The committee then played video footage of Mr Hawley running at a brisk pace through the Capitol building, then jogging down some stairs, as rioters entered the building.
The committee room, which was full of reporters, congressional aides, security staff and visitors, erupted with laughter when the footage was played.
Ms Luria said Capitol police had testified that Mr Hawley’s actions had “riled up” the crowd that day.
“We spoke with a Capitol police officer who was out there at the time. She told us that just Senator Hawley’s gesture riled up the crowd. And it bothered her greatly because he was doing it in a safe space, protected by the officers and the barriers,” the congresswoman said.
“Think about what we’ve seen,” she added. “Undeniable violence at the Capitol. The vice president being evacuated to safety by the Secret Service. Senators running through the hallways of the Senate to get away from the mob.”