19 U.S. Code § 2093 - Forfeiture of unlawful imports
Any pre-Columbian monumental or architectural sculpture or mural imported into the United States in violation of this chapter shall be seized and subject to forfeiture under the customs laws.
(b) Disposition of articles
Any pre-Columbian monumental or architectural sculpture or mural which is forfeited to the United States shall—
(1) first be offered for return to the country of origin and shall be returned if that country bears all expenses incurred incident to such return and complies with such other requirements relating to the return as the Secretary shall prescribe; or