That's according to a new report from the ACLU.
TSA behavioral detection
Credit: Joe Raedle/Getty Images

TSA agents are monitoring some passengers long after they leave the security line, according to a new report from the American Civil Liberties Union (ACLU).

The covert surveillance program extends throughout the terminal, and the ACLU claims it has helped foster abusive and racist behavior in some TSA agents. The group obtained documents through a Freedom of Information Act (FOIA) lawsuit.

The “behavior detection officers,” who can be dressed in plain clothing, examine travelers for “over 90 behaviors that the TSA associates with stress, fear, or deception,” according to the report.

The behaviors that could trigger TSA suspicion include yawning, whistling, rubbing hands together, or being late for a flight. Other more subjective behaviors include “wearing improper attire” or “displaying exaggerated emotions.” And sometimes advice is contradictory—passengers who have “no or little direct eye contact” or “widely open staring eyes” are equally suspicious.

When officers see a traveler exhibiting these behaviors, they “follow the travelers, subject them to additional screening, and at times bring in law enforcement officers who can investigate them further.”

Although the TSA says this is an effective program, the organization is in possession of “a significant body of research that contradicts those claims,” according to the ACLU, including “numerous academic studies and articles.”

The “SPOT” program (Screening Passengers by Observation Techniques) started in 2007 and was intended to monitor passengers waiting in the security line. But in 2009, the TSA expanded the program to the rest of the airport terminal.