Illegal Immigration:

INS Overstay Estimation Methods Need Improvement

PEMD-95-20: Published: Sep 26, 1995. Publicly Released: Oct 26, 1995.

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Pursuant to a congressional request, GAO examined the basis for the Immigration and Naturalization Service (INS) estimates of persons who entered the United States legally as visitors but did not leave under the terms of their admission.

GAO found that INS: (1) devised a creative approach for estimating overstays by estimating the number of uncounted departures; (2) determined that the number of uncounted departures could be estimated by using system data from countries for which it seems safe to assume there are few or no overstays; (3) applied its strategy using a global approach that requires the assumption that a single rate of system error applies to all countries worldwide; and (4) global approach provided a good starting point for estimating overstays, but INS should develop improved procedures for estimating overstays among foreign visitors arriving by air.

Recommendation for Executive Action

  1. Status: Closed - Implemented

    Comments: The GAO recommendation in PEMD-95-20, originally made by the Program Evaluation and Methodology Division, and thereafter assigned to the Applied Research and Methods team (ARM) is being closed because the Department of Homeland Security (DHS) made new estimates of overstays by air in its "Entry/Exit Overstay Report: Fiscal Year 2015," which it submitted to the Congress on January 19, 2016. As the report states, DHS submitted the report "Pursuant to the requirement contained in Division F, Title I of P.L. 114-113, the Consolidated Appropriations Act, 2016, and 8 U.S.C. 1376, the Department of Homeland Security is submitting this report on overstay data. This report is submitted to provide data on departures and overstays, by country, for foreign visitors who were admitted to the United States though air and sea Ports of Entry (POEs), and who were expected to depart in FY 2015 (October 1, 2014-September 30, 2015)." Although this report was not submitted to GAO in response to GAO's recommendation in PEMD-95-20 that DHS should make new estimates of overstays by air, the fact that DHS submitted such a report to the Congress, as a practical matter, closes this recommendation.

    Recommendation: The Commissioner, INS, should have new overstay estimates prepared for air arrivals from all countries, using improved estimation procedures such as those discussed in this report, including, as appropriate, the potential improvements suggested by INS or by reviewers of this report.

    Agency Affected: Department of Homeland Security: Directorate of Border and Transportation Security


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