http://en.wikipedia.org/wiki/Border_search_exception http://en.wikipedia.org/wiki/Border_search_exception You're required to present proof of citizenship and a

http://en.wikipedia.org/wiki/Border_search_exception http://en.wikipedia.org/wiki/Border_search_exception You're required to present proof of citizenship and allow a "routine" search of your belongings for contraband. A "non-routine" search requires them to have a reasonable suspicion about you specifically. My own reading is that a backscatter scan or s search of your body would count as non-routine, but of course a court may disagree.