In Smith v. California, the U.S. Supreme Court ruled that a city ordinance in Los Angeles was unconstitutional because it violated the First Amendment's freedom of speech protections. The case involved Eleazar Smith, a bookstore owner who had been convicted under this law for possessing an obscene book in his store. The ordinance held booksellers strictly liable for the content of books they sold, even if they were not aware of their contents. In its decision, the court emphasized that such strict liability would have a chilling effect on freedom of expression as it could lead to self-censorship by booksellers fearing prosecution. Therefore, it concluded that knowledge and intent must be proven before someone can be held accountable for disseminating obscene material.

In the dissenting opinion for Smith v. California, Justice Clark argued that the majority's decision to overturn Smith's conviction was based on a misinterpretation of both state law and precedent. He contended that Los Angeles Municipal Code § 311, under which Smith was convicted, did not require knowledge as an element of the offense but rather imposed strict liability on booksellers for selling obscene material. This interpretation aligned with previous Supreme Court rulings upholding similar laws against constitutional challenges. Furthermore, he disagreed with the majority’s view that such laws would have a chilling effect on freedom of speech or press because they only targeted obscenity which is not protected by First Amendment rights anyway. In his view, requiring proof of knowledge would make it nearly impossible to enforce obscenity laws and protect public morals effectively.