“American laws and American policy view the content of communications as the most private and the most valuable, but that is backward today,” said Marc Rotenberg, the executive director of the Electronic Privacy Information Center, a Washington group. “The information associated with communications today is often more significant than the communications itself, and the people who do the data mining know that.”
In the 1960s, when the NSA successfully intercepted the primitive car telephones used by Soviet leaders driving around Moscow in their Zil limousines, there was no chance the agency would accidentally pick up Americans.
Today, if it is scanning for a foreign politician’s Gmail account or hunting for the mobile phone number of a suspected terrorist, the possibilities for what the NSA calls “incidental” collection of Americans are far greater.
US laws restrict wiretapping and eavesdropping on the actual content of the communications of US citizens, but offer very little protection to the digital data thrown off by the telephone when a call is made. And they offer virtually no protection to other forms of nontelephone-related data, like credit card transactions.
Because of smartphones, tablets, social media sites, e-mail and other forms of digital communications, the world creates 2.5 quintillion bytes of new data daily, according to IBM. The computer giant estimates that 90 percent of the data that now exists in the world has been created in just the past two years. From now until 2020, the digital universe is expected to double every two years, according to a study by International Data Corp.
Accompanying that explosive growth has been rapid progress in the ability to manipulate the data.
When separate streams of data are integrated into large databases — matching, for example, time and location data from cellphones with credit card purchases or E-ZPass use — intelligence analysts are given a mosaic of a person’s life that would never be available from simply listening to their conversations. Just four data points about the location and time of a mobile phone call, a study published in Nature found, make it possible to identify the caller 95 percent of the time.
“We can find all sorts of correlations and patterns,” said one government computer scientist who spoke on condition of anonymity because he was not authorized to comment publicly. “There’ve been tremendous advances.”
When then-US president George W. Bush secretly began the NSA’s warrantless wiretapping program in October 2001, to listen in on the international telephone calls and e-mails of US citizens without court approval, the program was accompanied by large-scale data mining.
Those secret programs prompted a showdown in March 2004 between Bush White House officials and a group of top US Department of Justice and FBI officials in the hospital room of John Ashcroft, the then-attorney general.
Department of Justice lawyers, who were willing to go along with warrantless wiretapping, argued that the data mining raised greater constitutional concerns.