British researchers are developing a device that can detect lies in a subject’s facial expressions.
When people are hiding the truth, their eye movement patterns can suddenly change in response to questions they might not want to answer, such as whether they are carrying illegal drugs across borders. Facial expressions and facial blood flow can also change, said Hassan Ugail, head of visual computing research at England’s University of Bradford School of Informatics.
Ugail’s team is seeking to analyze these physical quirks in order to help border officers judge whether an individual is trying to conceal illegal drugs or other contraband.
A video camera scans a person’s face as he or she answers questions at passport control. It analyzes facial expressions and pupil changes while it looks for signs of deceit. Thermal cameras analyze blood flow in the subject’s face, seeking variations, which could occur if he or she is lying.
While trained customs and border security officers often can tell if people are lying just by looking at them, some smugglers are good actors who can retain their composure under stress, said Ugail. But the flow of blood to the face is difficult to control and would be detected by the thermal cameras, he said.
Computers automatically analyze the results of the scans using algorithms. If the project is successful, it could be integrated with current passport control procedures, Ugail said. Still in its early stages, there could be a number of other ways to use it, such as during police interviews.
The system requires no cooperation from the individual being scanned and analyzed, Ugail said. That sits in stark contrast to a lie detector test, in which a person is physically attached to a machine.
One possible flaw is false readings, which could happen in a number of scenarios, such as with a mentally ill individual or just someone with a high level of stress.
Ugail’s team is studying ways to address that problem.