Lansing, MI – A Michigan State Police Trooper was killed in the line of duty Wednesday, after being struck by a vehicle during a traffic stop. Trooper Joel Popp, of the Tri-City Post, and other troopers were investigating a suspected impaired driver who was stopped on northbound I-75 near Birch Run in a curved lane of travel. Another motorist, an 81-year-old male, struck two patrol cars and Popp, who was outside his patrol vehicle. Popp was transported to Hurley Medical Center where he succumbed to his injuries and passed away. The other driver had serious injuries but is expected to survive.