The House committee investigating the January 6th riot at the U.S. Capitol issued a subpoena Wednesday to a former Justice Department lawyer who aided Former President Donald Trump’s efforts to challenge the results of the presidential election.

The committee on Wednesday said it has demanded documents and testimony from Jeffrey Clark, a former assistant attorney general, who took interest in Trump’s baseless claims that the election results were fraudulent.

Clark clashed with superiors during the final weeks of the administration, including during a White House meeting.

The subpoena comes one week after the release of a Senate Judiciary Committee report that documented tensions within the senior ranks of the Justice Department as Trump and allies asked the agency to aid in efforts to undo the election.