clipped from: www.usatoday.com   
Airport security arsenal adds behavior detection
A Transportation Security Administration screener watches passengers at New York's JFK International Airport. Screeners are being taught ways to spot suspicious behavior in crowds.
a fast-growing but controversial security technique called behavior detection

The TSA has trained nearly 2,000 employees to use the tactic, which is raising alarms among civil libertarians and minorities who fear illegal arrests and ethnic profiling. It's also worrying researchers, including some in the Homeland Security Department, who say it's unproven and potentially ineffectual.

Doug Kinsey stands near the security line at Dulles International Airport, watching the passing crowd in silence. Suddenly, his eyes lock on a passenger in jeans and a baseball cap.

The man in his 20s looks around the terminal as though he's searching for something. He chews his fingernails and holds his boarding pass against his mouth, seemingly worried.

Kinsey, a Transportation Security Administration screener, huddles with his supervisor, Waverly Cousins, and the two agree: The man could be a problem. Kinsey moves in to talk to him.