Cal. Health & Safety Code § 110155

An authorized agent of the department shall have access to all records of carriers in commerce relating to the movement in commerce of any food, drug, device, or cosmetic, or the holding of that food, drug, device, or cosmetic during or after the movement, and the quantity, shipper, and consignee of the food, drug, device, or cosmetic. Evidence obtained under this section shall not be used in a criminal prosecution of the person from whom it is obtained. The carrier shall not be subject to the other provisions of this part by reason of their receipt, carriage, holding, or delivery of any food, drug, device, or cosmetic in the usual course of business as carriers.