Minn. Stat. § 42.13
Other than in legal actions charging failure to obtain a license and permit, the fact that a person holds a license or was issued a permit under sections 42.01 to 42.14, or that a person has complied with the rules made by the commissioner pursuant to sections 42.01 to 42.14, is not admissible as a defense in any legal action which may be brought under this section against such person.