After spending almost a billion dollars on a new system for fighting terrorism, the TSA may be turning into a backdoor immigration agency. The Intercept is reporting that the agency's new behavior detection program has drifted away from its intended focus on terrorism, with more than 90 percent of arrests having to do with immigration violations. (The survey looked at a single airport over a five-week period during 2007.) The behavioral detection program has been widely mocked for flagging supposedly suspicious behaviors like yawning and whistling, but the new report suggests the vague guidelines are serving a much more sinister purpose, effectively redirecting anti-terrorism measures towards immigration enforcement, even for domestic flights that don't involve travel outside the US.

It's unclear how much of the mission creep is intentional and how much is due to the relative prevalence of immigration violations compared to terrorism. Still, many of the behavioral guidelines seem to be actively flagging possible immigration violations, including checklist items for nervousness or separate individuals wearing similar clothing. "If you’re looking for people who exhibit multiple criteria on the checklist to reach the point of secondary screening or law enforcement referral," one official told The Intercept, "you’re just looking for illegal immigrants."