Adam DeMarco, a major in the D.C. National Guard, testifies before the House Committee on Natural Resources in July. He said the announcements U.S. Park Police directed toward protesters in Lafayette Square on June 1 were barely audible.

WASHINGTON, DC – JULY 28: Adam D. DeMarco, Major District of Columbia National Guard, testifies during the House Natural Resources Committee hearing on Unanswered Questions About the US Park Police’s June 1 Attack on Peaceful Protesters at Lafayette Square on July 28, 2020 in Washington, DC. (Photo by Bill Clark-Pool/Getty Images)