California Code, Health and Safety Code - HSC § 42408

(a) Any person who tampers with any ambient air monitoring equipment, including related recording equipment, owned or operated by a county, unified or regional air pollution control district, air quality management district, or by the State of California, is guilty of a misdemeanor, and is liable in a civil action for damages caused by the tampering to the owner or operator of the equipment.

(b) For purposes of this section, “tampering” means any unauthorized, intentional touching or other conduct affecting the operational status of monitoring equipment which has the potential to invalidate data collected from the monitoring activity.