WASHINGTON - The National Security Agency has been exploring options for relinquishing its database of telephone records that include searching across phone companies’ data for numbers linked to those of suspected terrorists and having the firms search daily against a watch list of suspect numbers, people briefed on the deliberations said.
The agency was expected to deliver to the White House this week some proposals for storing the data outside of government hands - a goal President Barack Obama announced in January to ease concerns about potential abuse of the agency’s vast store of records about Americans’ phone calls.
“At the end of the day, this is going to be a policy decision, with legal implementation,” Deputy Director Rick Ledgett said in a recent interview, noting that the agency does not make policy or law. “But what we’re doing, along with the [FBI], is advising on the parameters that would make the program valuable.”
Ledgett’s predecessor, John Inglis, spelled out four requirements to Congress for any new storage system: privacy protections, depth, breadth and agility. Ledgett added a fifth: value to the FBI.
“This program,” he said, “has to be useful to the FBI.” The National Security Agency collects data on phone calls, but not actual call content, to find clues to terrorist plots and networks.
Earlier this month, the Office of the Director of National Intelligence solicited ideas from industry to achieve, among other things, “near-simultaneous real-time access” to data across several providers. Obama asked the director of national intelligence and the attorney general to develop options by March 28.
The technology exists to carry out searches across several data systems linked in some fashion, industry and government officials said. That includes the ability to search beyond the first set of query results to retrieve the numbers of people who were in contact with those in the first set.
“The technologists at NSA who try to figure out how to do that say that it can be done,” said one former U.S. official who, like several others, spoke on the condition of anonymity to discuss sensitive matters. “It’s computationally difficult,” the official said. “But it’s doable.”
The House Intelligence Committee considered the option last year, and some members were comfortable with such searches as long as one phone company didn’t get information about a number from another phone company that it didn’t already have, an aide said. The Senate Intelligence Committee rejected the approach.
There also are policy and legal questions, including who would do the searching and what legal standard should be met before queries of the records are made.
The watch-list option would involve the agency providing suspect numbers to the phone companies to run against their databases. But the option would lack historic depth. Right now, the agency holds records for five years. Some phone companies hold data for less time, and those with flat-rate plans often do not keep toll records for billing purposes.
There would be no historical cache that might yield a link to a terrorist network. But, officials said, a National Security Agency analysis has shown that more than 75 percent of the cases where such data were useful involved records no older than two years.
The challenge, officials said, is to craft a solution that enables discovery of links to an overseas number of a suspected terrorist - to find out whether the person using that number has ever made a call to, or been called by a number in, the United States. Typically, phone companies cannot easily search for records of nonsubscribers. Doing so would take considerable time, industry officials said.
However, by pre-sorting the data so that they can be searched by the calling number and the called number, queries can be conducted faster, said Yaser Abu-Mostafa, a computer-science professor at the California Institute of Technology. From a technological perspective, he said, “my general impression is all of that would be a piece of cake for an organization with the type of resources that the NSA has.”
Front Section, Pages 3 on 02/21/2014