The Loudmouth (bottom centre image) is the 27th in the Turn Of Fate television short movies and is from 1958.
Jack Lemmon is the loudmouth and when he calls the police and confesses to a murder just to impress his friends, it backfires.
The police trace the call, he’s taken in for questioning and charged with three murders.
Did he commit them?
We don’t know but the moral of the story is don’t fool around because things can backfire.
Movie pages here.