California Code
ARTICLE 3 - Offenses Relating to Traffic Devices
Section 21467.

21467. Every prohibited sign, signal, device, or light is a public nuisance, and the Department of Transportation, members of the California Highway Patrol, and local authorities are hereby authorized and empowered without notice to remove the same, or cause the same to be removed, or the Director of Transportation, the commissioner, or local authorities may bring an action as provided by law to abate such nuisance.

(Amended by Stats. 1974, Ch. 545.)