The Fourth Amendment to the U.S. Constitution protects residents of the country against unreasonable searches and seizures by the government, but the NSA's large-scale collection of U.S. phone records doesn't amount to a search of those records, Byron said.
The telephone records collection program is limited in scope because the Foreign Intelligence Surveillance Court has to reauthorize it every three months, and it limits the number of hops NSA analysts can take from a suspect's telephone number to find other suspects, Bryant argued.
In addition, the NSA doesn't collect the content of U.S. phone calls, he noted. The NSA program collects so-called metadata about telephone calls sent and received, including time and date, as well as some phone call routing information.
"The protections are very important to understand," Byron said. The NSA program is "limited, and therefore, quite reasonable."
The program's scope eclipses any other law enforcement surveillance program that U.S. courts have had to deal with, argued Cindy Cohn, legal director at the Electronic Frontier Foundation. Cohn seemed to step back from Klayman's assertions that the NSA program allowed the agency to determine a suspect's location and other information collected in traditional wiretaps, but she emphasized the size of the NSA program, presumed to cover nearly all U.S. telephone records.
The program has collected the phone records of "millions of people over the period of many years," she said.
Judges questioned why they should rule against the NSA program when there's little difference in the information it collects, compared to traditional wiretap operations. Beyond that issue, telephone customers have "willingly transmitted" their call records to the carriers, added Judge David Sentelle.
The size of the program matters, Cohn said. "You can't decide everybody is a suspect always," she said. "The question is whether they have to find any kind of suspicion whatsoever."
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