Note: This is a very brief rundown of the Motion Picture Production Code. There are plenty of great books that provide a fuller history, such as Hollywood's Censor: Joseph I. Breen and the Production Code Administration by Thomas Doherty.
When It Happened One Night was released in February 1934, the Hays Code was almost 4 years old. However, the film is referred to as “pre-Code” which can be confusing, so allow me to explain.
In the 1920s—especially the late 1920s—Hollywood was becoming a breeding ground of scandal. Although studios did their best to keep these scandals out of the papers they couldn’t always succeed, especially when it came to alleged rapes and fatal drug overdoses. Hand-wringing studio executives were becoming increasingly nervous that families would begin to think of Hollywood films as something lewd and adult, thus cutting out a great deal of profits.
Censorship was already happening to varying degrees before the Hays Code. States and cities, as they do now, could ban films. But it was haphazard—what was perfectly acceptable in Detroit was banned in Boston. There were also different committees formed with the intention of forcing some kind of censorship on Hollywood or at least protesting what they saw as indecent in film. Notable of these groups was the Catholic Legion of Decency which remained powerful even after the implementation of the Hays Code, because films that got the stamp of approval from the Code could still be deemed indecent by the Legion which meant that the dollars of movie-going Catholics would be lost.
It became increasingly obvious that studios had to do something, and they preferred to create it and have autonomy rather than have the federal government enforce it upon them. Thus, in March 1930 the Hays Code was born, but it remained largely ignored by filmmakers until July 1934 when a new amendment mandated all films be submitted to the new Production Code Agency [PCA] for approval. This time between the code’s official existence and the mandated implementation of it is referred to as “Pre-Code.” So it’s a total misnomer, but if I’m being honest I can’t think of a better term.
This is where It Happened One Night finally comes in. But It Happened One Night was released months before the amendment was added to the Code so the film could have gotten away with a lot more than it did. However, filmmakers saw the writing on the wall and Capra, in choosing to more-or-less adhere to the code, ensured the lasting success of his movie.
It Happened One Night is a romantic comedy in which its male and female leads spend a great deal of time alone together. Unmarried. Spending the night in the same room. The problem was how to make it sexy without making it obscene or excessively passionate which were expressly forbidden according to the code: “Scenes of passion should not be introduced when not essential to the plot. In general, excessive passion should so be treated that these scenes do not stimulate the lower and baser element.” Scenes of passion were essential to this plot, but how to construct these scenes without stimulating the “lower and baser element”? The Walls of Jericho, of course.
When Peter and Ellie have to spend the night together for the first time, Peter drapes a blanket over a clothesline in the middle of the room and declares them the Walls of Jericho so that Ellie can have some privacy. By the end of the movie, much ado is made about the Walls of Jericho falling after they have fallen in love and are, for whatever reason, traveling together again. Not an inch of skin is shown, nor lips pressed together, but that blanket falling to the ground communicates all the sex that is needed.
The Walls also gave cinematography a chance to hint at the erotic. For example, when Ellie is changing, Colbert is down to her slip. According to Capra, he wanted Colbert to strip down more but she refused, leaving him to establish sexiness through silhouettes and shadows. I can’t help but wonder, though, if this wasn’t just Capra adhering to the code and wanting to attach a cute story to it [while protecting Colbert’s modesty].
In one scene which might have given censors pause, Gable is shirtless. According to this story, it was too difficult to nail the comedic timing the scene required while having too many layers of clothing, so he left the undershirt off [legend has it that sales of undershirts went down after the film’s release]. Lucky for us, the film was technically pre-Code and we get to see Gable’s chest in all of its glory. Because that’s the kind of thing that definitely stimulates the baser elements.