Hannigan

Easyriders Freedom F.I.G.H.T. (“Easyri-ders”), an unincorporated association of motorcycle enthusiasts, and fourteen individual California motorcycle riders brought suit against, inter alia, Maurice Hannigan, Commissioner of the California Highway Patrol (“CHP”), to enjoin the enforcement of the California motorcycle helmet law, Cal. Veh. Code §§ 27802-03 , which requires motorcycle drivers and passengers to wear helmets that comply with federal safety standards. Hannigan appeals the district court’s summary judgment grant of a permanent injunction, enjoining CHP from stopping any motorcyclists without reasonable suspicion that they are violating the helmet law, and from citing any motorcyclists without probable cause to believe that they have violated the helmet law. Easyriders cross-appeals the district court’s ruling on Hannigan’s motion for summary judgment that § 27803 is not unconstitutionally vague. We have jurisdiction pursuant to 28 U.S.C. § 1291 and affirm in part and reverse in part.

THE HELMET LAW

California Vehicle Code § 27803(b), which became effective in 1992, reads in relevant part:

Cal. Veh.Code. § 27803 (West Supp.1995). California Vehicle Code § 27802…