As the Devil Commands (1933)

Villain and hero in one... the more to be feared because he was Loved!

Slowly dying of an unspecified illness, wealthy invalid Charles Sellon wants his aide Neil Hamilton to end his suffering. Hamilton won't do it, but villainous lawyer Alan Dinehart, in line to inherit Sellon's millions, is not so charitable. Dinehart kills Sellon, then makes it look as though Hamilton murdered the old guy for his money.