There are 159 films with the same actors, 82 films with the same director, 66712 with the same cinematographic genres (including 8614 with exactly the same 2 genres than The Penal Code), to have finally 70 suggestions of similar films.
If you liked The Penal Code, you will probably like those similar films :
An orphan named Margery (Blanche Sweet) is working a dressmaking company in New York. She is sent to prison when a rich kleptomaniac named Helen North (Cleo Ridgely) puts some stolen lace in Margery's handbag. After leaving the prison she becomes a nurse for some time until the hospital she works at finds out she has a record. She leaves and becomes a nurse at a Red Cross emergency hospital in Belgium. At the same time, Helen has come to Belgium to take care of her sick father. After he dies, she is left without any money. She is planning to leave for California to live with her father's wealthy friend when an airship bomb sends Helen to the hospital Margery is working at. Another shell explodes and makes Margery think Helen is dead. Margery takes Helen's identity to go to California. She falls in love with a doctor named Richard Carlton (House Peters, Sr.) and right before they are supposed to get married Helen shows up. In order to stop people from taking Helen to the insane asylum, Margery confesses the truth. Carlton still wants to marry her anyway.
The wife of a poor shepard named Sue Wells (Cleo Ridgely) is tired of being poor and takes advantage of a loophole to become owner's of her neighbor's rich estate while her neighbor is gone. However, living in the mansion doesn't make Sue happy. When their neighbor comes home to find out what they've done he kills her husband. Right before he can kill her, she wakes up and realizes it was all a dream. Her husband then walks in and tells her that he got a job as that estate's overseer, so they won't have to worry about money anymore.