Scientists at Bradford University have developed a sophisticated new camera system that can detect lies just by watching facial changes.
Like a poker player the system picks up on tells, such as dilated pupils, biting or pressing together of the lips, wrinkling of the nose, breathing heavily, swallowing or blinking. And a thermal sensor can pick also up on non visible signs such as the swelling of blood vessels around the eyes.
The computerised system uses a simple video camera, a high-resolution thermal imaging sensor and a suite of algorithms. It successfully discriminates between truth and lies in about two-thirds of cases. Lead researcher Professor Hassan Ugail from Bradford University believes that he will eventually be able to reach a 90% accuracy level.
So far, the new system has only tested on volunteers. Researchers say the system could be a powerful aid to security services. Later this year, though, they plan to deploy it in a UK airport, probably running alongside experienced immigration officers as they conduct security interviews. The algorithms can then be tested against the verdicts of these officers.
This new system does have advantages over the polygraph. It is unobtrusive and quicker to use. And secondly the subject need not know that he or she is being tested. This, in theory, gives a more honest response.
But the researchers acknowledge, though, that these tests can never be 100% accurate. And so any use that is made must be done carefully, especially if it is to be used in security situations.