Fights like these are rare. For instance, Section 215 provision of the 2001 USA Patriot Act requires companies to turn over business records. The Justice Department said in a 2009 letter to Congress that between 2004 and 2007, no recipient such requests "has ever challenged the validity of the order."
Civil-liberties groups that have sued the government over suspected call-record programs and wiretapping, said they would use this week's new disclosures to bolster existing cases and possibly file new suits.
In particular, they plan to argue against two of the main defenses used by the Justice Department to date: that a full trial on the issues would be impossible without revealing "state secrets" and that consumers lack standing to sue because they cannot show impact from the spying programs. Privacy advocates say this week's disclosures puncture these defenses.
One factor that could become critical to any challenges against the NSA's domestic surveillance program is what the agency does with the information after it is collected.
"The NSA gathers a lot," said Stewart Baker, former general counsel of the NSA. "There are some fact patterns where there's no way you're going to catch terrorists without pooling this information somewhere where the government has access to it. It's likely that you impose restrictions not on the collection of the data, but on the search."
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