46 U.S.C. § 12131: Command of documented vessels

(a) In General.—Except as provided in subsection (b), a documented vessel may be placed under the command only of a citizen or noncitizen national (as such term is described in section 308 of the Immigration and Nationality Act (8 U.S.C. 1408)) of the United States. (b) Exceptions.—Subsection (a) does not apply to—(1) a vessel with only a recreational endorsement; or (2) an unmanned barge operating outside of the territorial waters of the United States.