"But even when no personal information intercepted by the NSA's computers make it to human eyes and ears, Rotenberg said, the mere fact that spy computers are monitoring the calls and e-mails may also violate the Fourth Amendment. The Supreme Court has never ruled on whether automated surveillance of phone calls and e-mails, without a warrant, is constitutional.
The closest comparisons, legal specialists said, are cases challenging the use of dogs and infrared detectors to look for drugs without a warrant. The Supreme Court approved the use of drug-sniffing dogs to examine luggage in an airport, but said police could not use infrared scanners to check houses for heat patterns that could signal an illegal drug operation."
http://www.boston.com/news/nation/wa...rseas_contacts