At international airports, it’s common for security checkpoints to include behavioral profiles–people who select passengers for additional screening due to body language or “behavioral indicators.” The practice, modeled on anti-terrorism practices at Israel’s Ben-Gurion Airport, is becoming more common in the United States due to a $878 million TSA pilot program . Although the TSA is keen on adoption of behavioral profiling, there’s a problem that may thwart the widespread adoption of the pilot program. A new report from the Government Accountability Office (GAO) claims behavioral profiling at airports doesn’t really work .

The GAO, Congress’s budget watchdog arm, sharply criticized the use of government funds to monitor body language at airports. In an almost 100-page report, the office said the TSA used unreliable data to fund its original billion-dollar pilot program. Most damningly, the report alleges that the behavior profiling–the different tics and odd behavior used to divert passengers to additional airport screening–varied wildly across airports. In polite bureaucratese, the TSA’s profilers were scolded for using “subjectivity” (in other words, gut feelings) instead of solid reasons to give passengers additional screening. According to the report, the TSA is at risk of funding a program with no scientific basis.

Additionally, the behavioral profiling model doesn’t really work in massive airports. The New York Times‘s editors astutely noted that Ben-Gurion airport is a medium-size airport with a manageable flow of travelers; at major hubs like JFK, LAX, or O’Hare, there’s so much traffic that profilers can only examine a small percentage of travelers.