The Transportation Security Administration has little evidence that an airport passenger screening program, which some employees believe is a magnet for racial profiling and has cost taxpayers nearly a billion dollars, screens passengers objectively, according to a report by the inspector general for the Homeland Security Department.

The TSA's "behavioral detection program" is supposed to rely on security officers who pull aside passengers who exhibit what are considered telltale signs of terrorists for additional screening and questioning. It is illegal to screen passengers because of their nationality, race, ethnicity or religion.

According to the report, the TSA has not assessed the effectiveness of the program, which has 2,800 employees and does not have a comprehensive training program. The TSA cannot "show that the program is cost-effective, or reasonably justify the program's expansion," the report said.

As a result of the TSA's ineffective oversight of the program, it "cannot ensure that passengers at U.S. airports are screened objectively," the report said.

In a statement Tuesday, the TSA said it had accepted six recommendations from the report.

The report, scheduled for release this week, was provided to the New York Times by a senior government official. The program has been under scrutiny for years. In 2010, the Government Accountability Office said that the program, which began in 2003, was started without first determining its potential effectiveness.

New York Times