Terror Database Has Quadrupled In Four Years, By Karen DeYoung, Washington Post Staff Writer

Each day, thousands of pieces of intelligence information from around the world — field reports, captured documents, news from foreign allies and sometimes idle gossip — arrive in a computer-filled office in McLean, where analysts feed them into the nation’s central list of terrorists and terrorism suspects.

Called TIDE, for Terrorist Identities Datamart Environment, the list is a storehouse for data about individuals that the intelligence community believes might harm the United States. It is the wellspring for watch lists distributed to airlines, law enforcement, border posts and U.S. consulates, created to close one of the key intelligence gaps revealed after Sept. 11, 2001: the failure of federal agencies to share what they knew about al-Qaeda operatives.

But in addressing one problem, TIDE has spawned others. Ballooning from fewer than 100,000 files in 2003 to about 435,000, the growing database threatens to overwhelm the people who manage it. …

TIDE has also created concerns about secrecy, errors and privacy. The list marks the first time foreigners and U.S. citizens are combined in an intelligence database. The bar for inclusion is low, and once someone is on the list, it is virtually impossible to get off it. At any stage, the process can lead to “horror stories” of mixed-up names and unconfirmed information, Travers acknowledged.

The watch lists fed by TIDE, used to monitor everyone entering the country or having even a casual encounter with federal, state and local law enforcement, have a higher bar. But they have become a source of irritation — and potentially more serious consequences — for many U.S. citizens and visitors.

In 2004 and 2005, misidentifications accounted for about half of the tens of thousands of times a traveler’s name triggered a watch-list hit, the Government Accountability Office reported in September. …

Sen. Ted Stevens (R-Alaska) said last year that his wife had been delayed repeatedly while airlines queried whether Catherine Stevens was the watch-listed Cat Stevens. The listing referred to the Britain-based pop singer who converted to Islam and changed his name to Yusuf Islam. The reason Islam is not allowed to fly to the United States is secret. [mjh: As long as Ted Stevens is suffering, I’m OK with this.] …

TIDE is a vacuum cleaner for both proven and unproven information, and its managers disclaim responsibility for how other agencies use the data. …

Every night at 10, TIDE dumps an unclassified version of that day’s harvest — names, dates of birth, countries of origin and passport information — into a database belonging to the FBI’s Terrorist Screening Center. TIDE’s most sensitive information is not included. The FBI adds data about U.S. suspects with no international ties for a combined daily total of 1,000 to 1,500 new names.