46 U.S.C. § 70503: Prohibited acts

manufacture or distribute, possess with intent to manufacture or distribute, or place or cause to be placed with intent to manufacture or distribute a controlled substance on board a covered vessel; destroy (including jettisoning any item or scuttling, burning, or hastily cleaning a vessel), or attempt or conspire to destroy, property that is subject to forfeiture under section 511(a) of the Comprehensive Drug Abuse Prevention and Control Act of 1970 ( 21 U.S.C. 881(a) ) on board a covered vessel; or conceal, or attempt or conspire to conceal, more than $100,000 in currency or other monetary instruments on the person of such individual while on board a covered vessel or in any conveyance, article of luggage, merchandise, or other container, or compartment of or aboard the covered vessel if that vessel is outfitted for smuggling. Subsection (a) applies even though the act is committed outside the territorial jurisdiction of the United States. a common or contract carrier or an employee of the carrier who possesses or distributes a controlled substance in the lawful and usual course of the carrier’s business; or a public vessel of the United States or an individual on board the vessel who possesses or distributes a controlled substance in the lawful course of the individual’s duties. Paragraph (1) applies only if the controlled substance is part of the cargo entered in the vessel’s manifest and is intended to be imported lawfully into the country of destination for scientific, medical, or other lawful purposes. The United States Government is not required to negative a defense provided by subsection (c) in a complaint, information, indictment, or other pleading or in a trial or other proceeding. The burden of going forward with the evidence supporting the defense is on the person claiming its benefit. a vessel of the United States or a vessel subject to the jurisdiction of the United States; or any other vessel if the individual is a citizen of the United States or a resident alien of the United States.