Convicted (1950)

During a barroom brawl, Joe Hufford (Glenn Ford) accidentally kills the son of a powerful, prominent man. The district attorney, George Knowland (Broderick Crawford), wins a manslaughter conviction, despite having doubts about the defendant's guilt. Joe is sent to prison, and George, who eventually becomes the warden there, hopes to get him released. But Joe gets so immersed in the culture and codes of the jailhouse that he finds it difficult to believe in his own innocence.