The ACLU filed an amicus brief on behalf of Gail Manning who appealed her conviction of a violation of section 316 of the Penal Code, in which, according to such code, she "did willfully and unlawfully keep a house used for the purpose of assignation or prostitution, and did let rooms, apartments, or tenements, knowing that it [sic] was to be used for the purpose of assignation or prostitution." She asserted that this language, written in 1872 and amended once between 1873-1874, was "overbroad and void for vagueness." The court agreed. However, the court decided that prostitution, in any language, is not legal and therefore the entire statute could not be dismissed.

The court writes: "The purported appeal from the order denying plaintiff's motion to strike the district attorney's return is dismissed. The order denying the petition for writ of mandate/prohibition is reversed, and the trial court is directed to issue a writ of mandate compelling defendant municipal court to sustain the demurrer to the complaint which charges plaintiff with violating section 316."