- Education and Science
How to detect a liar - non-verbal signs!
Everyone knows what lying is; when a person does not tell the truth; when a person is intentionally making a statement to deceive others. According to DePaulo et al. (1997) people tell one or two lies per day. The act of lying is classified in several categories. For example, there is big lie, bluffing, white lie, perjury, noble lie, polite lie, fabrication, barefaced lie, etc. Although, most people execrate lying, it is one of the most common wrong acts. Usually people lie to get themselves out of problems. It’s the fear that telling the truth might bring bad consequences for them. Sometimes people like to exaggerate to improve their self-image in the eyes of their surroundings or to get social acceptance. There are many reasons, but the question is; how do you know when someone is lying.
Although to catch a liar is not impossible, it is not as easy as we think. Experts such as FBI agents, psychiatrists or police officers are generally better at it, but there is a study that shows no difference in the accuracy rates of experts and non-experts (Bon & DePaulo, 2006).
There are certain non-verbal cues that give liars away.
Several studies have confirmed that when people are lying their voices become high. However, the difference in voice pitch can (usually) only be noticed if you know their normal voice pitch. Otherwise there is no certainty that the person is actually lying. Also, some people can be very calm when telling a lie and there voice pitch shows no fluctuations.
Speech errors and hesitations
Another indicator of lying is the frequency of speech errors. People make more speech errors, such as non-words (oh, erm), stuttering and stammering. Also, people give short responses with little detail, because coming up with a story takes more effort. They hesitate to give a proper reply and take breaks responding while thinking what to say next.
One of a popular sign that gives liars away is the movement of the eyes. Liars rarely look in the eye and tend to deny eye contact as much as possible. However, a practiced liar knows this sign too and will purposely make eye contact to seem more sincere.
A study by Ekman and Friesen (1974) has shown that body gives many cues away that are related to the deception of a liar. The participants gave identified a liar less accurately when a videotape of the face was shown than when a videotape of the body was shown. This means that body movements is a great source to detect liars. In another study Ekman suggested that food movements are an important indicator. However, other studies claim that as with hand movement, foot movement actually decreases, because people try to control any parts of the body which may reflect nervousness.
These are just few clues that might help to identify a lie. However, bear in mind that it is not always as easy as it may sound. Also, just because someone shows these signs does not mean that the person is lying. So, in order to detect a liar it is important to keep your eyes and ears open and think logically.