For the Defense (movie, 1930)

William Foster is a slick attorney who stays within the law, but specializes in representing crooks and shady characters. He's adept at keeping them out of jail, winning acquittals, and having decisions reversed, thus springing criminals out of prison. He is romantically involved with dancer Irene Manners, who is two-timing him, although she wants to marry him. She kills a man driving while out with her other man, Jack Defoe, who takes the blame. Unfortunately, a ring Foster had just given Irene is found at the crime scene. Foster ends up defending Jack, but when the ring is found, he thinks he is protecting Irene, so pleads guilty to jury tampering.