Today we clarify that the reasonableness of such searches does not depend, in whole or in part,
upon the consent of the passenger being searched
...
Thus, “where a Fourth Amendment intrusion serves special governmental needs, beyond the normal need for
law enforcement, it is necessary to balance the individual's privacy expectations against the
Government's interests to determine whether it is impractical to require a warrant or some level
of individualized suspicion in the particular context.”
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[R]equiring that a potential passenger be allowed to revoke consent to an ongoing airport security search makes little sense in apost-9/11 world. Such a rule would afford terrorists multiple opportunities to attempt to
penetrate airport security by “electing not to fly” on the cusp of detection until a vulnerable
portal is found. This rule would also allow terrorists a low-cost method of detecting
systematic vulnerabilities in airport security, knowledge that could be extremely valuable in
planning future attacks. Likewise, given that consent is not required, it makes little sense to
predicate the reasonableness of an administrative airport screening search on an irrevocable
implied consent theory. Rather, where an airport screening search is otherwise reasonable and
conducted pursuant to statutory authority, 49 U.S.C. § 44901, all that is required is the
passenger's election to attempt entry into the secured area 8 of an airport.