Frick and Frack brought their boat from Nassau to Miami. They re-entered the Miami port without going through customs. They docked the boat and began unloading it. Miami customs officials had observed the boat re-enter (by helicopter). When Frick and Frack began unloading the boat, customs officials sent in a team of officers to search the boat (no warrant). The officers discovered numerous bales of marijuana during the search and Frick and Frack were charged with drug possession and trafficking. They are now challenging the validity of the warrantless search. Discuss its validity.