At 5:40 a.m. before the Oct. 13, 2019, Chicago Marathon, a man armed with a loaded handgun was robbing passengers on a crowded train headed for downtown. A passenger at the back of that train car, 54-year-old Jean-Paul LaPierre, a storage facility manager from Weymouth, Massachusetts, saw the assailant approaching passengers nearer to the front of the car, but couldn’t immediately tell that it was a robbery. When the train stopped at the next station, nearly all the passengers disembarked. Following them, LaPierre asked what was happening. A fellow passenger told him about the gunman. LaPierre quickly followed the gunman, who was briskly walking to the next car in the train. Once aboard the second car, LaPierre pinned the gunman against a set of closed doors and pried the gun away from him. Another passenger took the gun from LaPierre and reset the safety on it. LaPierre secured the assailant until police arrived to arrest him. No passengers were injured, except for LaPierre who injured his arm in the encounter.