The NSA surveillance program involves an incredibly broad gathering of metadata about people’s conversations. Metadata doesn’t include the conversations themselves, just data about when and to whom they are made — i.e., not the content of the phone conversations but the phone numbers of the people having the conversations.
The key Fourth Amendment case at issue is Smith v. Maryland, 442 U.S. 745 (1979), which held that a pen register device capturing the phone numbers a person dialed wasn’t protected by the Fourth Amendment partly because the phone company had access to the phone numbers and partly because phone numbers weren’t viewed to be as sensitive as the phone conversations themselves.
The court in Klayman has an interesting view of why Smith v. Maryland is no longer applicable. Essentially, the court argues that the pen register information the government could gather when Smith was decided is much different from the very broad systematic gathering of phone records today.
The Klayman court relies on the U.S. Supreme Court’s fairly recent decision in United States v. Jones, 132 S.Ct. 945 (2012), where five justices in concurrences noted that wide-scale extensive surveillance technologies have different implications than there older more limited counterparts. Jones involved GPS, and the Court there distinguished an earlier case involving a beeper device that tracked a car. In a concurring opinion, Justice Alito wrote that “relatively short-term monitoring of a person’s movements on public streets accords with expectations of privacy that our society has recognized as reasonable. But the use of longer term GPS monitoring in investigations of most offenses impinges on expectations of privacy. For such offenses, society’s expectation has been that law enforcement agents and others would not—and indeed, in the main, simply could not—secretly monitor and catalogue every single movement of an individual’s car for a very long period.”
I find much merit to the Klayman court’s analysis. I have long argued that Smith was wrongly decided, and not too long ago, I wrote here about why there are strong privacy interests in metadata.