In the United States, film censorship and rating systems are primarily shaped by legal precedents and industry practices rather than direct government intervention. The First Amendment protects films as a form of free expression, following landmark rulings like Joseph Burstyn, Inc. v. Wilson in 1952, which overturned earlier restrictions on motion pictures. However, obscenity remains an exception under rulings such as Miller v. California (1973), allowing censorship of obscene material.

Historically, self-regulation played a major role in censorship. The Motion Picture Production Code (Hays Code) governed film content from the 1930s to the 1960s, enforcing moral guidelines. As social norms evolved, the Hays Code was replaced by the Motion Picture Association of America (MPAA) rating system in 1968. This voluntary system assigns ratings like G, PG, PG-13, R, and NC-17 based on content suitability for different age groups. While voluntary, economic pressures make ratings essential for mainstream distribution, as major studios and theaters often avoid unrated or NC-17 films.

       State and local censorship boards also historically regulated films but were largely abolished by the 1980s due to legal challenges. Today, filmmakers must navigate federal obscenity laws and industry ratings while balancing creative freedom with audience standards.