Only 1 percent of the 160,000 travelers pulled aside for TSA security pat downs or interviews based on the "behavior detection" technique used by airport screeners have been arrested and those have usually been on drug or fake ID charges, officials told USA Today.
"That's an awful lot of people being pulled aside and inconvenienced," Carnegie Mellon scientist Stephen Fienberg, who studied the TSA program and other counter-terrorism efforts, told the newspaper. "I think it's a sham. We have no evidence it works."
TSA spokeswoman Ellen Howe told the newspaper the program has been "incredibly effective" at catching criminals at airports, saying, "It definitely gets at things that other layers of security might miss."
TSA officials say the program has been expanded from 43 major airports last year to more than 150 airports, including some with as few as 20 flights per day, with the number of specially trained behavior officers rising from 2,470 to 3,400 by October.