A new book's behind-the-scenes look at Congress' Jan. 6 Capitol riot investigation

Denver Riggleman, a former Republican Congressman, joined the staff of the congressional committee investigating the Jan. 6, 2021 attack on the U.S. Capitol. His new book, "The Breach," describes his work on the investigation and his path to politics. (Steve Helber/AP)

Denver Riggleman served eight months as a senior technical adviser for the congressional select committee investigating the Jan. 6, 2021 attack on the U.S. Capitol. In a new book, titled "The Breach," Riggleman delves into a few key parts of the committee's investigation, including an examination of a trove of text messages sent and received by former White House chief of staff Mark Meadows in the lead-up to the Capitol riot. The book also revealed for the first time that during the Capitol breach, someone at the Trump White House made a call to a rioter who had entered the building.

Riggleman took a somewhat unusual path to the committee. After serving in the United States Air Force and working as a contractor for the National Security Agency, he ran for - and won - a seat in Congress representing a district in Virginia in 2018.