21. Proof of importer's statements
Where any question arises whether goods are to be treated as mentioned in regulation 11(3), the Comptroller may require the importer of the goods to furnish him or her, in such form as he or she may require proof of any statement made to him or her as to any fact necessary to determine that question, and if such proof is not furnished to his or her satisfaction, the question may be determined without regard to that statement.