The decision is today’s United States v. Cotterman (9th Cir. Mar. 8, 2013) (en banc). An excerpt from the court’s summary; note that most border searches can generally — for historical reasons — be done even without individualized suspicion, but here the court required such suspicion for computer searches:

[A] border search of a computer is not transformed into an “extended border search” requiring particularized suspicion simply because the device is transported and examined beyond the border…. [T]he fact that the forensic examination occurred 170 miles away from the border did not heighten the interference with the defendant’s privacy, and the extended border search doctrine does not apply, in this case in which the defendant’s computer never cleared customs and the defendant never regained possession….

[T]he forensic examination of the defendant’s computer required a showing of reasonable suspicion, a modest requirement in light of the Fourth Amendment…. [I]t is the comprehensive and intrusive nature of forensic examination — not the location of the examination — that is the key factor triggering the requirement of reasonable suspicion here…. [T]he uniquely sensitive nature of data on electronic devices, which often retain information far beyond the perceived point of erasure, carries with it a significant expectation of privacy and thus renders an exhaustive exploratory search more intrusive than with other forms of property….

[In this case,] the border agents had reasonable suspicion to conduct an initial search at the border (which turned up no incriminating material) and the forensic examination. The en banc court wrote that the defendant’s Treasury Enforcement Communication System alert, prior child-related conviction, frequent travels, crossing from a country known for sex tourism, and collection of electronic equipment, plus the parameters of the Operation Angel Watch program aimed at combating child sex tourism, taken collectively, gave rise to reasonable suspicion of criminal activity. …

[P]assword protection of files, which is ubiquitous among many law-abiding citizens, will not in isolation give rise to reasonable suspicion, but … password protection may be considered in the totality of the circumstances where, as here, there are other indicia of criminal activity…. [T]he existence of password-protected files is also relevant to assessing the reasonableness of the scope and duration of the search of the defendant’s computer…. [T]he examination of the defendant’s electronic devices was supported by reasonable suspicion and that the scope and manner of the search were reasonable under the Fourth Amendment.