LIE DETECTING MADE EASY

Can the suspect tell his story backwards?
If not, he's lying

Researchers from the University of Portsmouth claim that the best way to spot a lie is to make the suspect repeat his or her version of events in reverse order.


The researchers worked on the theory that it takes more effort to make up a story than it does to tell the truth. A subject asked to repeat a concocted series of events in reverse order would be under too much of a strain, they claimed, and would make mistakes.

Tricks of the Trade

Detectives use many psychological tricks to trip up liars. These betray obvious signals from shifting uncomfortably in a seat, through stumbling over words to failing to make eye contact. Another interview strategy used, the baseline method, requires investigators to note the way a suspect reacts to small talk before an interview compared with how he reacts to penetrating questions.

Behavioral Analysis

Finally there is the behavioural analysis strategy (BAI), in which interviewers compare the body language of liars and those telling the truth to set a list of questions.


Traditional police interview methods were used in the study, and in those that employed the reverse order tactics – described as “cognitive load interviews” – the interviewer asked the suspects to recall a series of events from the most recent backwards.


Officers were less likely to detect the liars when traditional methods were used in the interviews but were more likely to detect lies when the subjects were asked them to recall events in a reverse order.


The researchers believe that serial criminals are so well versed in police interviews that they know how to dodge the psychological tricks. But the reverse order method imposes an additional mental stress on liars.


Professor Aldert Vrij, one of the researchers, said: “Those [police officers] paying attention to visual cues proved significantly worse at distinguishing liars from those telling the truth than those looking for speech-related cues.

Success with Reverse Order Tactic

“Unlike truth-tellers, liars tend to tell their stories in a strict chronological time order and diverting from this order may well be too difficult for them to do,” Professor Vrij said.


“Lying takes a lot of mental effort in some situations, and we wanted to test the idea that introducing an extra demand would induce additional cues in liars. Analysis showed significantly more nonverbal cues occurring in the stories told in this way and, tellingly, police officers shown the interviews were better able to discriminate between truthful and false accounts.”



Information from Source:
http://www.timesonline.co.uk/tol/news/uk/science/article1895986.ece