Petitioner was charged with being a spectator at an illegal motor vehicle speed contest in violation of a San Diego city ordinance. He demurred to the complaint, arguing that the city’s authority to criminalize speed contest was preempted by Vehicle Code sections 23109, 23109.2, and 23109.5. The demurrer was overruled, and he sought a petition for writ of prohibition. The appellate court here denied the writ. The Vehicle Code sections dealing with speed contests and exhibitions are complimentary to and not in conflict with the San Diego Municipal Code sections dealing with spectators at such activities. The gathering of hundreds of spectators who engage in nuisance behavior is related to but not covered by the Vehicle Code sections.