Cal. Bus. & Prof. Code § 23109

Alcoholic beverages in continuous transit through this State are exempt from the provisions of this division only while in continuous transit through this State in the possession or custody of common carriers. The department may require affidavits of any person on forms prescribed by the department and may require any such shipments to be checked in and checked out at the boundaries of the State. Any person refusing to make the affidavits required or refusing to check in or check out the alcoholic beverages is guilty of a misdemeanor.