Data mining: What's the big deal?

Donna Leinwand Leger and Gary Strauss | USA TODAY

Metadata mining isn't the ultimate in Big Brother watching you.

But it's close.

Revelations that the National Security Agency is secretly collecting communications records of millions of Verizon customers showcases metadata mining — the practice of using computer algorithms to search vast collections of data for patterns.

Targeted data mining can be a useful tool for tracing terrorists, but there's no evidence that vacuuming up large amounts of everyday data and analyzing it for suspicious behavior is effective, says Elizabeth Goitein, co-director of the Liberty and National Security Program at the Brennan Center for Justice, a legal advocacy organization affiliated with New York University Law School.

Goitein compares it to police searching every house for criminals.

"Sure, they might find a criminal, but the Fourth Amendment stands for the idea that some invasions of privacy are not OK, even if it was a way to find criminals," she said.

The law hasn't kept up with new technology, says John Nockleby, director of the Civil Justice Program at Loyola Law School Los Angeles. The technology allows government investigators to not only map the target of an investigation but also everyone connected to that person.

"If they do this on a case-by-case basis, they are getting some localized information. It's a pinprick," Nockleby said. "But when they massively do it, they are enabling the government to search the human web of interconnectivity in a way that's never been possible before. The overarching issue of our time is to what degree do we want to allow the government to amass this kind of human interconnectivity in order to forestall the possibility of mass terrorist events."

Trouble arises when people with tangential connections become subjects of further investigation, Nockleby says. Checks and balances imposed in other investigations don't exist here, he said.

"There are going to be people swept up merely because the computer algorithms say they should be a target," he said. "So much of this rests on a blind faith that the government is comprised of good guys."

The order required Verizon to turn over phone numbers of both parties on a call, location data, time of the call, call duration, calling card numbers, call routing information and a unique cell phone call identifier called International Mobile Subscriber Identity number. While the order didn't permit the government to eavesdrop on calls, experts consider it intrusive.

"The way people use their cellphones today can paint an incredibly revealing picture of a person's personal life," Goitein says. When the data includes location, "you can paint a comprehensive picture of not just their associations, but their movements. If you have a record over time, that becomes extraordinarily personal — whether you're visiting your therapist or going to your AA meeting or if there is someone other than your husband or wife that you're visiting on a nightly basis."

In Goitein's view, the broad collection of data violates section 215 of the Patriot Act, which says government could gather this data only if it pertains to a terrorism investigation.

"I don't see any way that telling a major telecom subsidiary to give you all its customers' metadata" could be done in a way that section 215 envisioned, she said. "We've been told for years that these data collections may seem broad, but they are used in a targeted way to go after terrorists. We have proof now that it's not targeted to terrorist investigations."

Leslie Harris, president of the Center for Democracy and Technology (CDT), called the record-gathering "a massive abuse" of the Patriot Act. "The NSA is collecting the call records of Americans who have nothing to do with terrorism or terrorists and who pose no threat to U.S. national security," Harris said.

The National Security Agency and the Justice Department have said they are complying with the law.

CDT senior counsel Greg Nojeim said the data-mining operation, which expires July 19, may be "the broadest investigative program in U.S. history."

NSA's chief compliance officer, John DeLong, defended the agency's technology safeguards in a February article in FedTech magazine.

"The authorities, laws and policies we operate under are a sacred trust between the nation and the NSA," he wrote. "We treat compliance with the same respect. We're charged with delivering national security, but not at any price."

Verizon had no comment but said it was compelled to respond to the court. In its latest quarterly report, Verizon said it has more than 120 million customers, including almost 99 million wireless customers, 12 million residential lines and 10 million business lines.