The Ultimate Body Language Book

that is, police officers, interrogators, customs inspectors, federal law enforcement, federal polygraphers,
robbery investigators, judges, parole officers and psychiatrists fair only at slightly above the fifty
percent success rate. In fact, the average is somewhere around thirty-seven to seventy percent. It
doesn’t take a mathematician to realize that someone flipping a coin is just as skilled at coming up with
the correct answers as any one of the ‘experts’. Other research tells us that higher order interrogators
aren’t able to pass on their intuitive abilities to others, telling us that they can’t quantify their
observations. If they can’t pass it on to laypersons, than it’s of no practical purpose for me to pass it on
either. Other times programs specifically designed and sold to improve detection of deception have
failed miserably and have even lead to the detriment, rather than improvement of performance.
Several cues have been attributed to detecting lies. They generally fit into two broad classes. The first is
nonverbal visual cues such as facial expressions, eye blinking, eye contact or gaze aversion, head
movements, pupil dilation, nodding, smiling, hand movements or gestures, foot and leg movements and
postural shifts. The second includes paraverbal cues including pitch, pauses, or speech errors. We will
get into these cues in the following pages.
There are other ways that scientists use to detect lies and these involve machines. The most common is
the polygraph or lie detector machine. The polygraph relies on changes in heart rate, blood pressure and
increases in perspiration or respiration. However, these cues are of practically no use to us because they
are difficult, although not impossible to see. For example, an increase in heart rate can be seen if one
looks closely at the carotid artery that runs along the neck, and an increase in sweating does become
apparent with an increase in scratching of the palms. Further to this, the polygraph has a poor track
record and most experts agree that they have severe limitations and their accuracy is known to be
inconsistent. As well will see, one facet of lie detection involves the reading of nervousness, but
practiced pathological liars are skilled at eliminating nervousness, some even thrive on it thereby
reducing the propensity of visible and invisible cues.
Notwithstanding the myriad of hard fast research on lie detection, it is still a widespread belief in the
population that nonverbal behaviours betray a liar. Worldwide, cross-cultural comparison has shown a
universally held belief that liars are spotted through their bodies. Police training packages will often
include nonverbal and paraverbal behaviours as part of the ways in which deception can be detected. A
study by Lucy Akehurst of the University of Portsmouth found that when asked which behaviours they
thought would be consistent with lying, both police officers and regular lay people agreed. There was
no difference between what the experts thought betrayed a liar and what regular people thought. They
also agreed that these behavioural changes would occur more frequently in others as they lied, than in
themselves. This finding is replicated in other studies as well. For example, police officers and students
agreed on which behaviours were consistent with lying and they also thought that they themselves
would display these cues less during lying. The research therefore is inconsistent with the nature of
lying. It can not happen both ways, and it seems that our attitudes about lying and lie detection are
skewed.
Judgments of deception are heavily correlated with long held stereotypes. Person’s that display
behaviours associated with lying are often judged as deceptive even though they may be telling the
truth. Study after study shows that roughly only fifty percent of the time liars give themselves away, the
remaining time, liars are passed off as truth tellers and truth tellers as liars. Pegging liars based on body
language alone or some other mystical cue is a dangerous assumption. It can lead to marital break-ups
such as if a spouse falsely labels her husband as a cheater, can put innocent people in jail, can lead to
the firing of employees on suspicion of theft and so forth. Yet with this huge propensity for error and
consequence, we still, by in large, believe that we can read people on this trait. What shouldn’t surprise
us are the rewards achievable through lying and cheating. Lying can avoid punishment, save us from
hardships, but perhaps more importantly can help protect those around us and their feelings. The