The government's centralized terrorist watch list passed the 900,000 name mark this month, according to the ACLU, which estimated the new total by relying on Congressional testimony from the fall that the sprawling list was growing by 20,000 names a month.

The report the ACLU relied on to create its Watch List Counter included the following chart demonstrating the clear growth trajectory of the nation's centralized watch lists over the last several years.

The Terrorist Screening Center runs the list, accepting nominations of new names from a large range of government agencies.

Agencies use the watch list to check persons seeking visas, traveler entering or leaving the country, domestic airline passengers and persons stopped by state, local or federal law enforcement.

Most of the positive matches on the list came from police routinely checking persons, such as speeding motorists, according to the Government Accountability Office's report (.pdf). The number of individuals on the list is likely significantly less than 900,000, since the name count includes aliases.

Persons on the list are coded with varying suspected threat levels, so simply being on the watch list doesn't mean one will be arrested when say a person on the list pulled over for speeding. In fact, being on list isn't even enough to ensure that a person is denied a visa or entry into the country, according to the report.

The Transportation Security Agency exports two subsets of the list – the no-fly and selectee lists – which airlines use to decide who can get a boarding pass and who has to get hand-searched. The TSA continues to work on a much-delayed project now known as Secure Flight that would have the TSA perform the name checks in advance of a domestic flight, in an effort to reduce the number of falsely flagged travelers. Those affected over the last 7 years include many David Nelsons, a high-ranking nun, and federal employees with security clearances.

If the ACLU's math is correct, the list should pass the million name mark sometime in early July.

UPDATE: Terrorist Screening Center spokesman Chad Kolton dropped a long response in the comments, saying that the list is useful, contains actually more like 300,000 people due to aliases and that only some 5 percent – approximately 15,000, are U.S. persons.

[T]he Terrorist Screening Database (TSDB) is now the world’s most comprehensive and, importantly, widely-shared list of known and suspected terrorists. The names it includes are there because of credible information developed by our intelligence and law enforcement agencies, or those of our foreign partners. While the vast majority of people in it likely will never attempt to enter the United States, the TSDB gives our allies, consular officers, airlines, and border screening agencies the ability to make an informed decision about granting admission to the U.S. [...] We work hard to ensure that the list remains effective even as it grows. The government does its best to populate the TSDB with the identities of only those who are known or appropriately suspected of being involved in terrorism. In addition, TSC employees constantly review the database to remove the identities of those who have been cleared of any suspicion of engaging in terrorist activity. During fiscal year 2007 alone, TSC employees removed over 100,000 records from the database of individuals that had been cleared of having any nexus to terrorism. [...] This list helps protect Americans. We're always at work to do it in the most effective, least intrusive way we can, adhering to our important Constitutional principles in the process.

THREAT LEVEL confirmed that this was Kolton, and sent some further questions about the list and its operations to him. Due to some very reasonable extenuating circumstances, Kolton can't immediately answer, but THREAT LEVEL will bring you more in 10 days or so.

See Also: