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Terrorist watch lists: Are they working as they should?

Boston bombing suspect Tamerlan Tsarnaev was one of 875,000 names in a database the US uses to produce at least nine watch lists, but the naming didn't prevent the attack. Some security experts worry that data overload may be hindering US counterterrorism efforts.

By Staff writer / May 22, 2013

A Boston Fire Department team checks the crime scene near the Boston Marathon finish line. The name of one bombing suspect had been on US watch lists.

Kevork Djansezian/Getty Images


Tamerlan Tsarnaev landed on America's terrorist watch list in 2011. Tamerlan's younger brother, Dzhokhar, now charged in the Boston Marathon bombing case, seems not to have made the list.

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Ultimately, Tamerlan's inclusion on the watch list did not lead investigators to detect the April 15 bomb plot that killed three and wounded at least 260 – prompting inevitable questions about why not, and whether "dots" of intelligence and information that could have been connected were not.

America's terrorist watch list is all about connecting dots – and it is certain to be a focal point for future congressional hearings pegged to the Boston case. A key part of the vast counter-terrorism net cast by the federal government after the 9/11 attacks, the watch list is actually at least nine lists drawn from a single government database. Criteria for determining who gets "nominated" for inclusion in that database – and, then, who actually makes it onto an agency's specific list – are tightly guarded secrets.

What does seem clear, however, is that the spigot opened wide in the past three years, leading to torrential growth in the core terrorism database. Whether those extra mounds of data give investigators a more accurate view of the universe of terrorists, or whether they have the unintended effect of making prospective terrorists harder to find and the dots harder to connect, is a matter of hot debate – and one that the Boston bombing case may well intensify.

"There's absolutely no question that they're just choking on the volume of information, both classified and unclassified, that's going into the system," says Dakota Rudesill, a visiting professor at Georgetown University Law Center who served, during President Obama's first term, as special assistant in the policy, plans, and requirements directorate of the Office of the Director of National Intelligence, which includes the National Counterterrorism Center. "You're taking on this immense challenge with all this data – like finding a particular needle in a haystack of needles."

US officials bridle at inferences that the system is overwhelmed.

"Certainly, the volume has grown, and the list has grown for a number of reasons," says a US counterterrorism official who spoke on background because he is not permitted to speak on the record. "The intelligence is better; the value of sharing information is seen as better by the agencies involved. The watch list is created specifically to be one of the big dot-connectors in the counterterrorism effort – it's among the most sophisticated systems the government has – and it's proven itself to be effective."

The making of the watch lists

Like a giant digital vacuum, the Terrorist Identities Datamart Environment (TIDE), a highly classified database maintained by the National Counterterrorism Center in McLean, Va., each day sweeps up thousands of names, aliases, birth dates, and other potential terrorist tidbits – known as "derogatory information" – and tries to match them with hundreds of thousands of names, faces, and identifying biometric data also sent in by the Central Intelligence Agency, the State Department, the Federal Bureau of Investigation, and other US agencies.


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