Before John Zera, Hales Corners Detective Howard Hingiss had only handled one murder case. While he narrowed down the suspect list, with the help of the F.B.I. and other departments, he would never discover the identity of the murderer. Twenty-five years after his retirement, and almost 40 years after the crime, the question of who killed John remains unsolved.

For more information on the true crime series Unsolved: A murder mystery podcast, visit http://usatoday.com/unsolved.

For more reporting on cold cases, unsolved cases and true crime detectives, as well as additional true crime stories and investigative journalism visit witness.usatoday.com. Crime reporter and investigative reporter Gina Barton is also host of Untested: A true crime podcast, in which Annie Harrison joins the rank of true crime detectives as she solves the cold case of a possible serial rapist. Subscribe to Untested: A true crime podcast at https://art19.com/shows/untested

See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.