Utah Code Title 58. Occupations and Professions § 58-37-15. Burden of proof in proceedings on violations--Enforcement officers exempt from liability

(1) It is not necessary for the state to negate any exemption or exception set forth in this act  1 in any complaint, information, indictment or other pleading or trial, hearing, or other proceeding under this act, and the burden of proof of any exemption or exception is upon the person claiming its benefit.

(2) In absence of proof that a person is the duly authorized holder of an appropriate license, registration, order form, or prescription issued under this act, he shall be presumed not to be the holder of a license, registration, order form, or prescription, and the burden of proof is upon him to rebut the presumption.

(3) No liability shall be imposed upon any duly authorized state or federal officer engaged in the enforcement of this act who is engaged in the enforcement of any law, municipal ordinance, or regulation relating to controlled substances.