It was reported today that a city business man was jailed for just two years (instead of a possible ten years) for spiking the drink of a female banker. The offence was noted by an eagle eyed waiter who spotted the banker's slight of hand into her drink whilst the female banker had gone to the ladies; she was thankfully alerted as to what had happened.
This is an extreme criminal case, but just how good are we generally at spotting deception? Research would suggest that people are not as good at spotting deception as they would like to think they are. Indeed studies show that people can detect lies in others at a rate of only 44%. This is actually lower than the success rate you would get if you tossed a coin! Even professionals who are meant to have a lot of specific experience in this area, like police officers and customs officials, perform no better at lie detection than at the level of chance.
In one famous experiment police officers were exposed to videotapes of people who were asking the general public for help in finding their missing relatives. Some of these people had been found guilty of crimes against their relatives, but police officers didn’t know this. What was found was that none of them performed any better at spotting deceit at the press conference than could be expected by chance. The psychologist Professor Aldert Vrij from the University of Portsmouth, who conducted the experiment found that the only professionals more adept at spotting deception than the general public were officers who worked for the US Secret Service – but then again they tended to trust no one at all!
One explanation as to why professionals are no better at detecting lies than the general public is that they are burdened with the same false beliefs about how liars behave. For example, it is commonly assumed that liars have key non-verbal behaviours, such as gaze aversion. This preconception remains, despite psychological research which has established that this is not a reliable indicator of deception. In fact, the opposite may hold sway, because liars have to manufacture reality, and this usually requires a lot more intellectual effort than simply reporting the truth. As well as watching their words, liars tend to closely monitor how their story is coming over, hence liars tend to watch the listeners closely rather than look away. Therefore, perhaps someone who maintains more eye contact than usual, is the person to be concerned about. Also, good liars tend to make fewer gestures to try and ensure that they don’t ‘leak’ body language clues.
It is said that a useful tip is that liars experience three main emotions during lying: fear of being caught, excitement at the opportunity of fooling someone (‘duping delight’) and guilt. Hence by being vigilant for these emotions, you are supposedly more likely to spot them in the form of ‘micro’ expressions – facial movements that appear for short periods of time and betray these emotions. Unfortunately, these expressions are usually barely perceptible.
So, beware of preconceived ideas as to who is telling the truth, and always be aware of the dangers of leaving your drink unattended in a public place.