Comment by greenduck

Expanding on what katbyte said, the Hays code was adopted by every major studio in the US to replace state run censors. They did this because of the same battle going on right now in social media: "if we self regulate, then we won't need government regulation placed on us." When an entire industry agrees to follow the code and has enforcement options available and does it with the threat of government action if they don't follow it, the only difference between it and a real law are the name. The consequences to ignoring it were that your funding was dropped, the offending scenes were removed from the film, or you were kicked out and blacklisted from the industry. They were apparently pretty strict about it. You can tell that by how stringently it was followed for decades.