The TSA earlier this year suspended Secure Flight, the U.S. government's second attempt at a preflight screening program for domestic airlines following the terrorist attacks of Sept. 11, 2001. An earlier system, called the Computer-Assisted Passenger Prescreening System, was created in 2003 and abandoned in 2004 because of privacy concerns.

"In early 2006, TSA suspended development of Secure Flight and initiated a reassessment," Cathleen Berrick, director of the GAO's homeland security and justice division, said in a written statement to the House Homeland Security Intelligence Subcommittee in June. Her comments came in response to written questions from members of the subcommittee.

The TSA now expects to complete its reassessment of the screening program before the end of September (download PDF). Whatever direction Secure Flight takes, Berrick said the TSA needs to follow a disciplined development approach that fully defines system requirements, schedule and costs, she said. In addition, the TSA must test the system to ensure that it functions as intended, establish privacy protocols and access to a redress process, Berrick said.

"As we stated in our February 2006 testimony, over the last three years, the TSA has faced a number of challenges in developing and implementing Secure Flight to ensure the program operates effectively," Berrick said.

To ensure the effectiveness of the program, Berrick said the TSA also needs to assess name-matching technologies that would be used to vet passenger names against names in the Terrorist Screening Database. That would help the agency learn more about how the technologies work in real-world situations.