A: Any agency can nominate a person to the list, but the FBI and CIA screen all nominations and make the final decisions. The FBI has said if there is enough evidence against a person to open a preliminary FBI investigation because of suspected terrorist links, that name will be placed on the list. An anonymous phone call about someone isn't enough by itself. The CIA has said its standards are somewhat subjective.
Q: How does someone get off the list?
A: If an FBI investigation determines a person has no link to terrorism, that name will be removed from the list. The CIA has refused to tell congressional investigators its standards for removal.
Q. Who operates the list?
A. The FBI's Terrorist Screening Center maintains and distributes the list, or parts of it, to other federal agencies that use it to screen travelers and even to 750,000 state and local police who can access it to check people they stop.
Q: Is the terrorist watch list the same as other programs, such as the ones used in airports for air travel?
A: Not exactly. The no-fly list which can keep a traveler from boarding a plane and the selectee list which tags domestic airline passengers for extra searching and questioning at airports are much smaller portions of the terrorist watch list. It takes more evidence of terrorist links to get on these smaller sections of the list than it does to get on the full list.
Q: Do any other agencies use the list?
A: Yes. The State Department consular service, which issues travel visas to foreigners who want to visit the U.S., gets a version of the list that includes everyone but U.S. citizens and legal immigrants. The Customs and Border Protection agency uses the full list to screen arriving and departing international travelers on planes and ships.
Q: Are there ways to get off these lists?
A: Yes, there are ways to get off the full watch list and the smaller portions of it used by Homeland Security Department agencies like the Transportation Security Administration.
The FBI's Terrorist Screening Center has a redress program where people can request to be removed from the list. But that process takes an average of 67 days.
The Homeland Security Department's redress program, DHS TRIP, processes appeals as well. Since that office opened Feb. 26, it has received 16,000 requests for redress, and 7,400 of those have been completed. Each request takes about 44 days to process, and people can track the progress of their requests online. Most of the people who appeal are not actually on the terrorist watch list, but they were misidentified at the airport usually because they have a name similar to someone who is on the watch list.
Q: Is there any relief for those people who are constantly being stopped because authorities are confusing them with someone on a version of the list?
A: The DHS TRIP program puts such people on a so-called cleared list that is circulated to the airlines.
Customs and Border Protection operates its own cleared list for international travelers, called Primary Lookout Override. It's a computerized system that automatically suppresses a match on Customs computers at the borders the next time a person who previously generated a false match is encountered (unless new derogatory information has come in). From inception in February 2006 through September 2007, Customs has put 71,487 names on the override list.
Q. With all these checks, why do so many people get mistakenly stopped or questioned — sometimes repeatedly — trying to board domestic airplane flights?
A. Matching names without biometric identifiers like fingerprints will always generate some mistakes. In addition, screening for domestic air travelers is now done by each airline. They don't all have immediate access to the most updated no-fly or selected lists or cleared lists, and they have different procedures.
Q. Can't this be improved?
A. DHS says its proposed Secure Flight program would be a substantial improvement. The government would take over matching passenger names with watch lists from the airlines. DHS says then screeners would all use up-to-date lists and the same procedures and standards for everyone.
Q. When will Secure Flight begin?
A. It was scheduled to begin its testing this fall but is short of money. DHS says if Congress doesn't approve the $74 million President Bush has requested for the program, it will have to delay tests, suspend contracts and postpone the rollout. With prompt funding, DHS says it could implement Secure Flight sometime next year.
Q: Has the watch list led to arrests of terrorists?
A: Yes, a few. But the government has never issued a precise figure on the number. It also has led to arrests of people for other crimes. And it has barred people from entering the United States, including in 2006 alone, 269 foreigners judged to present an unacceptable risk of committing a terrorist act.