In an era that is spawning so much escapist cinema, this film is an awesome contemporary social critique. The film is one of the first to pinpoint a social hot button issue and exploit it in public onscreen. You feel the injustice of the time coming out of the actor and the story.
By this point the Great depression has reshaped Hollywood as almost completely escapist films, stories that take you out of your chair into another universe and use on-location shooting, camera movement and high quality film to make you lose your sense of reality and escape it. This film does that but also challenges current social conventions, an oddity in the American market at the time that seemed to be turning its back on exploring core issues in the country.
This film explores the issues of corruption in the justice system, racism, and institutionalized incarceration. It was so impactful that the movie spawned litigation and legislation to correct the problems of modern prisons in America and the abuse of the correctional system by the powers that run it.
Soviet films had this direct effect with their films in affecting change but it was different because it was state-sponsored and European filmmakers were challenging hundreds of years of aristocratic convention that were not really the norm in America, a country of immigrants. This film directly challenged the currently legal system of the United States, an early Edward Snowden effect, which was immense for the time.
The film has such a haunting ending, a testament to Paul Muni's exceptional acting, when he slips away into the darkness after being asked "How do you live?" and responds, "I steal." It speaks entirely to the condition of the impoverished American worker who at this point in history has to start thinking about crime as a way to make ends meet even though he doesn't want to. It's the system that has failed him not his own morals.