Coleman, D-Houston, has represented House District 147 since 1993. He serves as chair of the House County Affairs Committee and sits on the Public Health Committee. He has also served as chair of the Legislative Study Group since 2003. In the 85th Legislative Session, Coleman authored the House version of the Sandra Bland Act, which includes de-escalation training for officers, improves the process to make a complaint or compliment of an officer, jail diversion, jail safety, improved data collection, and improvements to mental healthcare. He is also a past chair and current member of the Texas Legislative Black Caucus.