Terrorist Screening Database

The Terrorist Screening Database or TSDB is the central terrorist watchlist consolidated by the FBI's Terrorist Screening Center and used by multiple agencies to compile their specific watchlists and for screening. As of June 2016^[update] the list is estimated to contain over 2,484,442 records, consisting of 1,877,133 individual identities. Approximately 1,600 nominations are suggested daily, 600 names are removed and 4,800 records are modified by the U.S. intelligence community. Approximately one out of twenty of the people on the list are U.S. citizens or legal permanent residents.

The TSDB is fed from two primary sources: international terrorist (IT) information from the Terrorist Identities Datamart Environment, a central database on known or suspected international terrorists maintained by the National Counterterrorism Center (NCTC) and domestic terrorist (DT) information from the Federal Bureau of Investigation (FBI). The TSDB in turn is used to compile various watchlists and screening systems:

The Justice Department's Office of Inspector General has criticized the list for frequent errors and slow response to complaints. An audit by the Office of Inspector General found that 38% of a 105 record sample contained inaccuracies. The Federal Bureau of Investigation has said it is redressing errors, and a 2006 review of the no-fly list reduced its size by half, from 71,872 records to 34,230 records.

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