Yawning, blinking and sweating ... hmmm!

The US airport security agency is facing ridicule after leaked documents revealed its checklist of tell-tale signs that a passenger might be a potential terrorist.

Despite its own report finding that the human ability to identify deceptive behaviour through body language is no better than chance, the US government has spent almost $1 billion on a programme deploying Behaviour Detection Officers to airport security.

The specialised agents of the Transportation Security Administration (TSA) are taught to evaluate passengers based on a checklist known as the “Screening of Passengers by Observation Techniques” (SPOT).

But according to a copy of a SPOT report published by The Intercept, the “stress factors” that could see passengers stopped at security include arriving late for your flight, blinking too much, sweating and “excessive yawning”.