50 CFR § 14.53 - Detention and refusal of clearance.
(a) Detention. Any Service officer, or Customs officer acting under § 14.54, may detain imported or exported wildlife and any associated property. As soon as practicable following the importation or exportation and decision to detain, the Service will mail a notice of detention by registered or certified mail, return receipt requested, to the importer or consignee, or exporter, if known or easily ascertainable. Such notice must describe the detained wildlife or other property, indicate the reason for the detention, describe the general nature of the tests or inquiries to be conducted, and indicate that if the releasability of the wildlife has not been determined within 30 days after the date of the notice, or a longer period if specifically stated, that the Service will deem the wildlife to be seized and will issue no further notification of seizure.
(b) Refusal of clearance. Any Service officer may refuse clearance of imported or exported wildlife and any Customs officer acting under § 14.54 may refuse clearance of imported wildlife when there are responsible grounds to believe that:
(1) A Federal law or regulation has been violated;
(2) The correct identity and country of origin of the wildlife has not been established (in such cases, the burden is upon the owner, importer, exporter, consignor, or consignee to establish such identity by scientific name to the species level or, if any subspecies is protected by the laws of this country or the country of origin to the subspecies level);
(3) Any permit, license, or other documentation required for clearance of such wildlife is not available, is not currently valid, has been suspended or revoked, or is not authentic;
(5) The importer, exporter, or the importer's or exporter's agent has not paid any fee or portion of balance due for inspection fees required by § 14.93 or § 14.94, or penalties assessed against the importer or exporter under 50 CFR part 11. This paragraph does not apply to penalty assessments on appeal in accordance with the provisions of part 11.