Leon Krol was a criminal who was the first person on the scene following the murder of police officer Sean "Coop" Cooper in 1968. Krol spotted a brick of heroin in the back seat of Coop's patrol car with a black harp stamped on it, identifying it as being from known drug dealer Teddy Burke. Krol took the heroin and fled shortly before Owen Murphy arrived. It's unclear if Krol was released, though his information did lead to the closing of Coop's case. Krol has most likely since died.