After retiring from the NFL, Haller returned to Michigan State University and became a police officer with the Michigan State University Department of Police and Public Safety. He spent 13 years on the force, eventually working his way up to 1st Lieutenant of the Uniform Division. In 2006, Haller, along with athletic director Mark Hollis, men's basketball coach Tom Izzo, and former athletic director Ron Mason, was a member of the selection team that brought head football coach Mark Dantonio to Michigan State.
