Based on the popular radio show that lasted from 1939 through 1951. The initial TV version (1951-'52) was staged as a live bi-weekly series and rebooted in 1954. The District Attorney of Los Angeles 'protects' the people.
Joe Kogan, a nice guy but who has a reputation as an habitual liar, is a witness to the hit-and-run death of a bookie's runner. When the bookie learns about Joe, uses Joe's reputation to discredit him, then tries to frame him for a jewel robbery.