The authorities aren’t looking; one can proceed without fear of getting caught. Several writers hold that this term comes from the days of piracy and smuggling, when it declared the absence of coast guards. However, one of the earliest references dates from 1530, appearing in J. Palsgrave’s book about the French language: “The kynge intendeth to go to Calays, but we must first clere the costes.” By the late sixteenth century the term was also being used figuratively. Eric Partridge regarded it as a cliché from the eighteenth century on.