	Background

Each year, millions of visitors, foreign students, and immigrants come to  the United States. Visitors may enter on a legal temporary basis—that is,  with an authorized period of admission that expires on a specific date—  either with temporary visas (generally for tourism, business, or work)  issued by the Department of State or, in some cases, as tourists or  business visitors who are allowed to enter without visas. The latter group  includes Canadians and qualified visitors from 27 countries who enter  under the Visa Waiver Permanent program. The large majority of these  visitors depart on time, but others overstay. When visiting the United States for business or pleasure, two major groups  are exempt from filling out an I-94 form:
Mexicans entering the United States with a Border Crossing Card (BCC) at  the Southwestern border who intend to limit their stay to less than 72  hours and not to travel beyond a set perimeter (generally, 25 miles from  the border) and
Canadians admitted for up to 6 months without a perimeter restriction.Thus, the majority of Canadian and Mexican visits cannot be tracked by  the current system, because the visitors have not filled out Form I-94. The Extent of Overstaying Is Significant and May Be Understated by DHS’s Estimate

Significant numbers of visitors overstay their authorized periods of  admission. As indicated above, many short-term  overstays are not included in the 2000 census, which is the starting  point of DHS’s 2.3 million estimate of the resident overstay population. Missing departure forms. One weakness is the inability to match some departure  forms back to corresponding arrival forms. Because of these weaknesses, DHS has no accurate list of overstays to  send to consular officials or DHS inspectors. . .  interior enforcement.” Despite large  numbers of overstays, current efforts to deport them are generally limited  to (1) criminals and smugglers, (2) employees identified as illegal at  critical infrastructure locations, and (3) persons included in special  control efforts such as the domestic registration (or “call in” component)  of the NSEERS program (the National Security Entry and Exit Registration  System). US-VISIT, the U.S. Visitor and Immigrant Status Indicator Technology, is  DHS’s new tracking system intended to improve entry-exit data. Overstay Issues May Complicate Efforts to Ensure Domestic Security

		Tracking System Weaknesses Encourage Overstays and Hamper Some Counterterrorism Efforts

Tracking system weaknesses may encourage overstaying on the part of  visitors and potential terrorists who legally enter the United States. Additionally, a current overstay recently pled guilty to identity document  fraud in connection with the 9/11 hijackers. Conclusion

Weaknesses in DHS’s current overstay tracking system and the magnitude  of the overstay problem make it more difficult to ensure domestic security. Viewing our results in the context of  our nation’s layered defense, we believe that improvements in the tracking  system must work together with other factors—such as intelligence,  investigation, and information-sharing—to help ensure domestic security. 2.
Why GAO Did This Study

Each year, millions of visitors, foreign students, and immigrants come to the United States. Visitors may enter on a legal temporary basis--that is, with an authorized period of admission that expires on a specific date--either (1) with temporary visas (generally for tourism,business,or work) or, in some cases (2) as tourists or business visitors who are allowed to enter without visas. (The latter group includes Canadians and qualified visitors from 27 countries who enter under the visa waiver program.) The majority of visitors who are tracked depart on time, but others overstay. Four of the 9/11 hijackers who entered the United States with legal visas overstayed their authorized periods of admission. This has heightened attention to issues such as (1) the extent of overstaying, (2) weaknesses in our current overstay tracking system, and (3) how the tracking system weaknesses and the level of overstaying might affect domestic security.

What GAO Found

Significant numbers of foreign visitors overstay their authorized periods of admission. The Department of Homeland Security estimates the resident overstay population at 2.3 million as of January 2000. Because the starting point for this estimate is the 2000 census, it does not cover short-term overstays who have not established residence here. It also omits an unknown number of potential long-term overstays from Mexico and Canada. Because of unresolved weaknesses in DHS's current system for tracking arrivals and departures (e.g.,noncollection of some departure forms and inability to match other departure forms to arrivals), there is no accurate list of overstays. Two new tracking initiatives are intended to address these weaknesses. NSEERS, the National Security Entry and Exit Registration System, does not cover most visitors. US-VISIT, the U.S. Visitor and Immigrant Status Indicator Technology, a more comprehensive,automated program, is being phased in. While its design and implementation face a number of challenges, evaluating US-VISIT against the weaknesses GAO identifies here would increase its potential for success. The current tracking system's weaknesses limit control options and make it difficult to monitor potential terrorists who enter the country legally. Like other illegal immigrants, overstays obtain jobs with fraudulent identity documents, including jobs at critical infrastructure locations, such as airports. Thus, tracking issues can affect domestic security and are one component of a layered national defense. Improving the tracking system could work with intelligence, investigation, information-sharing, and other factors to help counter threats from foreign terrorists.