The Detective (1968)

When a gay man is viciously slain, Detective Joe Leland (Frank Sinatra) is put on the case. Joe eventually tracks down the victim's roommate, who confesses to the crime and is sentenced to death; however, the outcome of the case doesn't sit well with the detective. Norma (Jacqueline Bisset), a distraught widow, visits Joe. She believes her husband's death was no accident, but the cops don't seem to care. Joe begins to investigate, and stumbles on a cover-up related to his previous case.