Here is a very cool "Fourth amendment" T shirt, underpants etc to wear when flying, for those who do not approve of the "naked" body scanners and generally think that the anti-terrorist paranoia means the terrorists have won. The person at the scanning machine will see the US fourth amendment in appear on the scanner screen. 4th Amendment per above seems to be about respecting peoples integrity and not harrassing them with searches unless there is very good reason to suspect them of a crime.