An old-fashioned pencil might be a better way to work out whether people are telling the truth than a high-tech lie detector. Aldert Vrij from the University of Portsmouth got 31 people from the police and military to go on a mock mission to pick up a package from another agent and deliver it elsewhere. Half the participants were told to tell the truth about their mission while the other half were asked to lie. The participants were also asked to draw the scene of the package pick up. The 'liars' tended not to draw the agent whom they had picked up the package from whereas the 'truth tellers' did. 80% of truth tellers and 87% of liars could be correctly classified on this basis alone. The truth tellers were equally divided (53% vs 47%) between those who drew the scene from a first-person perspective and those who drew it from a birds-eye view whereas the liars nearly all (81%) went for a birds-eye view. The accuracy of the drawing test was actually better than other psychological tests or lie detectors.
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