The Amazing Dr. Clitterhouse

The Amazing Dr. Clitterhouse is a movie starring Edward G. Robinson, Humphrey Bogart, and Claire Trevor. A brilliant Park Avenue doctor becomes a criminal in order to do research into the criminal mind.
A wealthy society doctor decides to research the medical aspects of criminal behaviour by becoming one himself. He joins a gang of thieves and proceeds to wrest leadership of the gang away from it's extremely resentful leader.