California Code, Penal Code - PEN § 594.5

Nothing in this code shall invalidate an ordinance of, nor be construed to prohibit the adoption of an ordinance by, a city, city and county, or county, if the ordinance regulates the sale of aerosol containers of paint or other liquid substances capable of defacing property or sets forth civil administrative regulations, procedures, or civil penalties governing the placement of graffiti or other inscribed material on public or private, real or personal property.