Customs Modernization and Tariff Act
Section 222. Authority to Search Vehicles, Other Carriers, Persons and Animals. - Upon reasonable cause, any person exercising police authority may open and examine any box, trunk, envelope, or other container for purposes of determining the presence of dutiable or prohibited goods. This authority includes the search of receptacles used for the transport of human remains and dead animals. Such authority likewise includes the power to stop, search, and examine any vehicle or carrier, person or animal suspected of holding or conveying dutiable or prohibited goods.