Former congressman Adam Kinzinger (R-Ill.), a vocal critic of former president Donald Trump, will speak at the Democratic convention, according to a person familiar with the schedule who spoke on the condition of anonymity to discuss plans that haven’t been made public. Kinzinger, who served on the House select committee that investigated the Jan. 6, 2021, attack on the U.S. Capitol, previously endorsed President Joe Biden before the incumbent withdrew from the race.