Skip to main content

Aviation Security: Rapid Growth in Expedited Passenger Screening Highlights Need to Plan Effective Security Assessments

GAO-15-150 Published: Dec 12, 2014. Publicly Released: Dec 12, 2014.
Jump To:
Skip to Highlights


What GAO Found

Since the Transportation Security Administration (TSA) implemented its expedited screening program—known as TSA Pre✓TM in 2011, the number of passengers receiving expedited screening grew slowly, and then increased about 300 percent in October 2013 when TSA expanded its use of methods to increase passenger participation, such as conducting automated risk assessments of all passengers. In conducting these assessments, TSA assigns passenger scores based upon information available to TSA to identify low risk passengers eligible for expedited screening for a specific flight prior to the passengers’ arrival at the airport.

To assess whether a passenger is eligible for expedited screening, TSA considers (1) inclusion on an approved TSA Pre✓TM list of known travelers; (2) results from the automated risk assessments of all passengers; and (3) threat assessments of passengers conducted at airport checkpoints known as Managed Inclusion. Managed Inclusion uses several layers of security, including procedures that randomly select passengers for expedited screening, behavior detection officers who observe passengers to identify high-risk behaviors, and either passenger screening canine teams or explosives trace detection devices to help ensure that passengers selected for expedited screening have not handled explosive material. Prior to Managed Inclusion’s implementation, TSA relied primarily on approved lists of known travelers to determine passenger eligibility for expedited screening.

TSA has tested the effectiveness of individual Managed Inclusion security layers and determined that each layer provides effective security. GAO has previously conducted work on several of the layers used in the Managed Inclusion process, raising concerns regarding its effectiveness and recommending actions to TSA to strengthen them. For example, in January 2013, GAO recommended that TSA take actions to comprehensively assess the effectiveness of canine teams. TSA subsequently addressed this recommendation by conducting the assessment. In October 2014, TSA planned to begin testing Managed Inclusion as an overall system, but could not provide specifics or a plan or documentation showing how the testing is to be conducted, the locations where it is to occur, how these locations are to be selected, or the timeframes for conducting testing at each location. Moreover, GAO has previously reported on challenges TSA has faced in designing studies to test the security effectiveness of its other programs in accordance with established methodological practices such as ensuring an adequate sample size or randomly selecting items in a study to ensure the results can be generalizable—key features of established evaluation design practices. Ensuring its planned testing of the Managed Inclusion process adheres to established evaluation design practices will help TSA provide reasonable assurance that the testing will yield reliable results.

This is a public version of a sensitive report that GAO issued in September 2014. Information that the Department of Homeland Security deemed sensitive has been removed.

Why GAO Did This Study

TSA screens or oversees the screening of more than 650 million passengers annually at more than 450 U.S. airports. In 2011, TSA began providing expedited screening to selected passengers as part of its overall emphasis on risk-based security. Specifically, by determining passenger risk prior to travel, TSA intended to focus screening resources on higher-risk passengers while expediting screening for lower-risk passengers.

GAO was asked to determine how TSA implemented and expanded expedited screening via TSA Pre✓TM. This report examines, among other things, (1) how TSA has developed, implemented, and used expedited screening, (2) how TSA assesses passenger risk, and (3) the extent to which TSA has determined the Managed Inclusion system's effectiveness. GAO analyzed TSA procedures and data from October 2011 through January 2014 on expedited screening and interviewed officials at TSA, airport authorities, air carriers, and industry associations about expedited screening.


GAO recommends that TSA take steps to ensure and document that its planned testing of the Managed Inclusion system adheres to established evaluation design practices, among other things. DHS concurred with GAO's recommendations.

Recommendations for Executive Action

Agency Affected Recommendation Status
Transportation Security Administration To ensure that TSA's planned testing yields reliable results, the TSA Administrator should take steps to ensure that TSA's planned effectiveness testing of the Managed Inclusion process adheres to established evaluation design practices.
Closed – Implemented
In 2015 we found that TSA was conducting an expedited screening process, referred to as Managed Inclusion, without having tested its security effectiveness. At the time of our report TSA told us they had plans to test the Managed Inclusion process, and we recommended the TSA Administrator ensure that TSA's planned effectiveness testing of the Managed Inclusion process adhere to established evaluation design practices. Subsequent to our report, TSA updated part of the Managed Inclusion process to include Real Time Threat Assessment (RTTA), which was used along with Managed Inclusion to increase the number of passengers receiving expedited screening. Over the summer of 2016 TSA conducted a study to determine the security effectiveness of combining these two processes into a single screening approach, now referred to as Canine Expedited Screening (CES). In late 2017, TSA provided documentation showing the design and results of their study to determine the security effectiveness of the CES process. We compared TSA's security effectiveness evaluation with criteria for evaluation design, and determined that TSA's design adhered to the established evaluation design practices. We determined TSA's documentation was sufficient to show their evaluation design adhered to GAO criteria, and as such we are closing this recommendation as implemented.
Transportation Security Administration To ensure that TSA has accurate information by which to measure the performance of its expedited screening programs, the TSA Administrator should ensure that the expedited screening performance goals and measures align.
Closed – Implemented
In November 2015, the TSA Administrator approved a new expedited screening goal and measure, and based on our analysis, the new goal and measure are aligned. The new expedited screening goal requires TSA to increase the number of travelers included on one of the TSA PreCheck lists of low-risk passenger populations to 25 million travelers. The TSA PreCheck lists include travelers enrolled in TSA's PreCheck Application Program and Custom and Border Protection's Trusted Traveler Programs, and TSA and Department of Defense employees, among others. To measure progress towards this goal, TSA tracks the number of travelers who are included on each PreCheck list. As of December 2015, almost nine million travelers are included on these lists according to TSA documents. TSA estimates that the TSA PreCheck lists will include 25 million travelers in 3 to 5 years and plans to expand and facilitate the inclusion of additional lists of low-risk populations as trusted travelers, use contractors to provide enrollment services for the TSA PreCheck Application Program, and increase marketing and communication efforts to reach the 25 million vetted traveler goal.

Full Report

Office of Public Affairs


Airport securityAirportsAviation securityEligibility determinationsPassenger screeningProgram evaluationProgram managementRisk assessmentRisk managementSecure flightSecurity assessmentsTransportation securityHomeland security