CA Penal Code Section 315

Every person who keeps a house of ill-fame in this state, resorted to for the purposes of prostitution or lewdness, or who willfully resides in such house, is guilty of a misdemeanor; and in all prosecutions for keeping or resorting to such a house common repute may be received as competent evidence of the character of the house, the purpose for which it is kept or used, and the character of the women inhabiting or resorting to it.