Cal. Health & Safety Code § 106500

(a) The chief and those inspectors of the Food and Drug Section as he or she may designate, are peace officers for the purpose only of carrying out the duties of their employment. The authority of the peace officer shall extend to any place in the state as to any public offense committed, or which there is reasonable cause to believe has been committed, within this state that is a violation of any provision of Division 8.5 (commencing with Section 22950) of the Business and Professions Code, Part 5 (commencing with Section 109875), or the Miscellaneous Food, Food Facility, and Hazardous Substances Act (Section 27), or Chapter 4 (commencing with Section 41301) of Division 16 of the Food and Agricultural Code. This authority shall further extend to violations of any penal provision of this code, the Business and Professions Code, or the Penal Code, that are discovered in the course of and arise in connection with the employment of these officers.
(b) Any inspector of the Food and Drug Section shall have the authority, as a public officer, to arrest, without a warrant, any person who, in his or her presence, has violated, or as to whom there is probable cause to believe has violated, any provision of Part 5 (commencing with Section 109875) or the Miscellaneous Food, Food Facility, and Hazardous Substances Act (Section 27), or Chapter 4 (commencing with Section 41301) of Division 16 of the Food and Agricultural Code.
In any case in which an arrest authorized by this subdivision is made for an offense declared to be a misdemeanor, and the person arrested does not demand to be taken before a magistrate, the arresting inspector may, instead of taking the person before a magistrate, follow the procedure prescribed by Chapter 5C (commencing with Section 853.5) of Title 3 of Part 2 of the Penal Code. That chapter shall thereafter apply with reference to any proceeding based upon the issuance of a citation pursuant to this authority.
(c) There shall be no civil liability on the part of and no cause of action shall arise against any person, acting pursuant to subdivision (b) and within the scope of his or her authority, for false arrest or false imprisonment arising out of any arrest that is lawful or that the arresting inspector, at the time of the arrest, had reasonable cause to believe was lawful. No inspector shall be deemed an aggressor or lose his or her right to self-defense by the use of reasonable force to effect the arrest or to prevent escape or to overcome resistance.
(d) The chief and inspectors of the Food and Drug Section may serve all processes and notices throughout the state.