The Moonlighter (1953)

Wes Anderson (Fred MacMurray) is caught cattle rustling and promptly jailed. The public is outraged, but, since Wes always worked at night, they don't know what he looks like. Still, they break into the prison and lynch a hobo they think is Wes, while the actual culprit sneaks off to see his old flame, Rela (Barbara Stanwyck), who has recently taken up with his straitlaced brother, Tom (William Ching). But Tom is envious of his outlaw brother, and he decides to join Wes in a life of crime.