Convicted

Broderick Crawford plays a district attorney that reluctantly prosecutes a defendant for accidentally killing a man in a fist fight in defense of a lady's honor. Realizing that Ford was being severely under-defended by his own lawyer, Crawford tries to pass every break in the book to the defense attorney, who's too stupid to pick up on it. In the end, Ford is convicted of murder and sentenced to prison. Later, Crawford is assigned as the new warden and attempts to help Ford further.

This is a very good, highly underrated movie. It's worth a look.