Investigator Michael W. Ridges, a 29-year-old investigator with the Cook County Sheriff's Police Department, was killed on October 17, 1985, in Forest Park, Illinois. Ridges had served five years with the department and was investigating a string of vandalism incidents around a Prospect Heights home when he noticed a car with three men who matched the vandal descriptions. He called in the vehicle description and stopped the car to check the occupants’ identities.

While checking the men, one produced a concealed gun and shot Ridges once in the head and once in the hand, fatally wounding him. The three suspects were apprehended shortly afterward, aided by Ridges’ radio description and a witness account. Court outcomes reported include a life sentence for one suspect and a 40-year sentence for another. Ridges was survived by his wife and is remembered by colleagues and the community he served.