Originally Posted by
ralfp
What's the legal justification for such searches (i.e. what logic did courts use to claim that such searches are constitutionally permissible?) Searches of inbound aircraft... that I can understand (sort of), but outbound?
Outbound border searches have been upheld by courts for as long as inbound ones. There are plenty of laws which regulate what people can export and what paperwork they have to file to do so.
For example, 31 USC 5317(b):
Searches at Border.— For purposes of ensuring compliance with the requirements of section 5316, a customs officer may stop and search, at the border and without a search warrant, any vehicle, vessel, aircraft, or other conveyance, any envelope or other container, and any person entering or departing from the United States.