Pursuant to Homeland Security Presidential Directive 6, the Attorney General established TSC in September 2003 to consolidate the government’s approach to terrorism screening and provide for the appropriate and lawful use of terrorist information in screening processes. TSC’s consolidated watch list is the U.S. government’s master repository for all records of known or appropriately suspected international and domestic terrorists used for watch list-related screening. When an individual makes an airline reservation, arrives at a U.S. port of entry, or applies for a U.S. visa, or is stopped by state or local police within the United States, the frontline screening agency or airline conducts a name-based search of the individual against applicable terrorist watch list records. In general, when the computerized name-matching system of an airline or screening agency generates a “hit” (a potential name match) against a watch list record, the airline or agency is to review each potential match. Any obvious mismatches (negative matches) are to be resolved by the airline or agency, if possible, as discussed in our September 2006 report on terrorist watch list screening. However, clearly positive or exact matches and matches that are inconclusive (difficult to verify) generally are to be referred to TSC to confirm whether the individual is a match to the watch list record. TSC is to refer positive and inconclusive matches to the FBI to provide an opportunity for a counterterrorism response. Deciding what action to take, if any, can involve collaboration among the frontline screening agency, the National Counterterrorism Center or other intelligence community members, and the FBI or other investigative agencies. If necessary, a member of an FBI Joint Terrorism Task Force can respond in person to interview and obtain additional information about the person encountered. In other cases, the FBI will rely on the screening agency and other law enforcement agencies—such as U.S. Immigration and Customs Enforcement—to respond and collect information. Figure 1 presents a general overview of the process used to resolve encounters with individuals on the terrorist watch list. To build upon and provide additional guidance related to Homeland Security Presidential Directive 6, in August 2004, the President signed Homeland Security Presidential Directive 11. Among other things, this directive required the Secretary of Homeland Security—in coordination with the heads of appropriate federal departments and agencies—to submit two reports to the President (through the Assistant to the President for Homeland Security) related to the government’s approach to terrorist- related screening. The first report was to outline a strategy to enhance the effectiveness of terrorist-related screening activities by developing comprehensive and coordinated procedures and capabilities. The second report was to provide a prioritized investment and implementation plan for detecting and interdicting suspected terrorists and terrorist activities. Specifically, the plan was to describe the “scope, governance, principles, outcomes, milestones, training objectives, metrics, costs, and schedule of activities” to implement the U.S. government’s terrorism-related screening policies. The National Counterterrorism Center and the FBI rely upon standards of reasonableness in determining which individuals are appropriate for inclusion on TSC’s consolidated watch list. In accordance with Homeland Security Presidential Directive 6, TSC’s watch list is to contain information about individuals “known or appropriately suspected to be or have been engaged in conduct constituting, in preparation for, in aid of, or related to terrorism.” In implementing this directive, the National Counterterrorism Center and the FBI strive to ensure that individuals who are reasonably suspected of having possible links to terrorism—in addition to individuals with known links—are nominated for inclusion on the watch list. To determine if the suspicions are reasonable, the National Counterterrorism Center and the FBI are to assess all available information on the individual. According to the National Counterterrorism Center, determining whether to nominate an individual can involve some level of subjectivity. Nonetheless, any individual reasonably suspected of having links to terrorist activities is to be nominated to the list and remain on it until the FBI or the agency that supplied the information supporting the nomination, such as one of the intelligence agencies, determines the person is not a threat and should be removed from the list. Moreover, according to the FBI, individuals who are subjects of ongoing FBI counterterrorism investigations are generally nominated to TSC for inclusion on the watch list, including persons who are being preliminarily investigated to determine if they have links to terrorism. In determining whether to open an investigation, the FBI uses guidelines established by the Attorney General. These guidelines contain specific standards for opening investigations, including formal review and approval processes. According to FBI officials, there must be a “reasonable indication” of involvement in terrorism before opening an investigation. The FBI noted, for example, that it is not sufficient to open an investigation based solely on a neighbor’s complaint or an anonymous tip or phone call. If an investigation does not establish a terrorism link, the FBI generally is to close the investigation and request that TSC remove the person from the watch list. Based on these standards, the number of records in TSC’s consolidated watch list has increased from about 158,000 records in June 2004 to about 755,000 records as of May 2007 (see fig. 2). It is important to note that the total number of records in TSC’s watch list does not represent the total number of individuals on the watch list. Rather, if an individual has one or more known aliases, the watch list will contain multiple records for the same individual. TSC’s watch list database is updated daily with new nominations, modifications to existing records, and deletions. Because individuals can be added to the list based on reasonable suspicion, inclusion on the list does not automatically prohibit an individual from, for example, obtaining a visa or entering the United States when the person is identified by a screening agency. Rather, when an individual on the list is encountered, agency officials are to assess the threat the person poses to determine what action to take, if any. From December 2003 (when TSC began operations) through May 2007, screening and law enforcement agencies encountered individuals who were positively matched to watch list records approximately 53,000 times, according TSC data. A breakdown of these encounters shows that the number of matches has increased each year—from 4,876 during the first 10-month period of TSC’s operations to 14,938 during fiscal year 2005, to 19,887 during fiscal year 2006. This increase can be attributed partly to the growth in the number of records in the consolidated terrorist watch list and partly to the increase in the number of agencies that use the list for screening purposes. Our analysis of TSC data also indicates that many individuals were encountered multiple times. For example, a truck driver who regularly crossed the U.S.-Canada border or an individual who frequently took international flights could each account for multiple encounters. Further, TSC data show that the highest percentage of encounters involved screening within the United States by a state or local law enforcement agency, U.S. government investigative agency, or other governmental entity. The next highest percentage involved border-related encounters, such as passengers on airline flights inbound from outside the United States or individuals screened at land ports of entry. The lowest percentage of encounters occurred outside of the United States. The watch list has enhanced the U.S. government’s counterterrorism efforts by allowing federal, state, and local screening and law enforcement officials to obtain information to help them make better-informed decisions during encounters regarding the level of threat a person poses and the appropriate response to take, if any. The specific outcomes of encounters with individuals on the watch list are based on the government’s overall assessment of the intelligence and investigative information that supports the watch list record and any additional information that may be obtained during the encounter. Our analysis of data on the outcomes of encounters revealed that agencies took a range of actions, such as arresting individuals, denying others entry into the United States, and most commonly, releasing the individuals following questioning and information gathering. TSC data show that agencies reported arresting many subjects of watch list records for various reasons, such as the individual having an outstanding arrest warrant or the individual’s behavior or actions during the encounter. TSC data also indicated that some of the arrests were based on terrorism grounds. TSC data show that when visa applicants were positively matched to terrorist watch list records, the outcomes included visas denied, visas issued (because the consular officer did not find any statutory basis for inadmissibility), and visa ineligibility waived. Transportation Security Administration data show that when airline passengers were positively matched to the No Fly or Selectee lists, the vast majority of matches were to the Selectee list. Other outcomes included individuals matched to the No Fly list and denied boarding (did not fly) and individuals matched to the No Fly list after the aircraft was in flight. Additional information on individuals on the watch list passing undetected through agency screening is presented later in this statement. U.S. Customs and Border Protection data show that a number of nonimmigrant aliens encountered at U.S. ports of entry were positively matched to terrorist watch list records. For many of the encounters, the agency determined there was sufficient information related to watch list records to preclude admission under terrorism grounds. However, for most of the encounters, the agency determined that there was not sufficient information related to the records to preclude admission. TSC data show that state or local law enforcement officials have encountered individuals who were positively matched to terrorist watch list records thousands of times. Although data on the actual outcomes of these encounters were not available, the vast majority involved watch list records that indicated that the individuals were released, unless there were reasons other than terrorism-related grounds for arresting or detaining the individuals, such as the individual having an outstanding arrest warrant. Also, according to federal officials, encounters with individuals who were positively matched to the watch list assisted government efforts in tracking the respective person’s movements or activities and provided the opportunity to collect additional information about the individual. The information collected was shared with agents conducting counterterrorism investigations and with the intelligence community for use in analyzing threats.