My experience is that many Private Aircraft terminals, such as private jets, private helicopters, etc, don't screen passengers, or their luggage, the way the public is searched in "Commercial Aircraft" pre-flight screening.

http://www.theatlantic.com/magazine/archive/2011/01/private-...

http://www.generalaviationnews.com/2011/01/is-ga-a-menace/

The above links discuss the matter further.