Before revision: Since flying the Q flag involves a request for boarding by Port State Control, it has also become an invitation to Customs to inspect a vessel for dutiable goods or contraband, as in the "Rich Harvest " case, where a yacht carrying a large quantity of alcohol flew the Q flag in order to seek exemption from having to pay duty during a temporary visit to port.
After revision: Since flying the Q flag involves a request for boarding by Port State Control, it has also become an invitation to Customs to inspect a vessel for dutiable goods or contraband, as in the Rich Harvest case, where a yacht carrying a large quantity of alcohol flew the Q flag in order to seek exemption from having to pay duty during a temporary visit to port.