Barry Loudermilk, a Republican member of Congress, led an unofficial tour through the House office buildings about a day before the Capitol attack.
The tour included a man who took photos of the tunnel entrances and the US Capitol police checkpoint and then joined thousands of Donald Trump supporters to march on the Capitol the next day.
The person's activities were captured on security cameras and turned over to the House select committee. The footage was made public on Wednesday in a letter to Loudermilk.
The allegation from Democrats that the tour was a preparation for the Capitol attack is supported by the footage showing the man and others stopping to take pictures.
It cast doubt on Loudermilk's previous claims that he did not lead a tour on January 6. Loudermilk initially denied that he led a tour and then said he gave a tour to about 16 people.
The video evidence challenged a recent letter from the US Capitol police chief who told Loudermilk that the activities they observed were not suspicious.
Tours were banned at the time due to Covid measures. Members of Congress, staff, reporters, US Capitol police and official business visitors should have been in the Capitol that day.
Members of Congress bend the rules as they please. Two sources said that if a member wanted to give a tour, they could have given one name to the appointments desk and let everyone in.
The select committee said in the letter that the Loudermilk tour was cleared by a staffer. The group would most likely have visited Loudermilk's office as an official visit, but instead took the scenic route on the way in or out.
The sources said that the group might have been authorized to be in the complex. The names of the entire group would be in the possession of the House sergeant at arms if they were not recorded.
The Capitol dome, managed by Lauren Boebert on 12 December 2020, has since returned to the Capitol, though the procedure is more stringent and visitors must be submitted.
According to the select committee, Loudermilk led an hours-long tour of the Rayburn, Cannon and Longworth House office buildings, as well as the tunnels leading from Rayburn and Longworth to the Capitol building itself.
In a letter to Loudermilk, the chairman of the panel, Bennie Thompson, wrote that individuals on the tour photographed and recorded areas of the complex that are not usually of interest to tourists. Concerns about their activity and intent were raised by the January 5 tour.
Some of the people on Loudermilk's tour attended the Save America rally on the morning of January 6, when Trump spoke and urged his supporters to march to the Capitol.
The panel said the man that took a photograph of a staircase in Longworth, located next to a hallway leading to one of the tunnels, joined the march to the Capitol and threatened members of Congress.
The man said that there was no escape for Pelosi, Schumer, and Nadler. They are coming in like white on rice for everyone. We're going to pull you out by your hair.
Loudermilk refused to cooperate with the committee last month as he denied any wrongdoing. The tour group took pictures of the areas in the letter.