Although we are better at detecting deception verbally, rather than through non-verbal cues, we tend to trust and rely on and use body language more when discerning if someone is being truthful e.g., if someone says – genuinely – that they are really excited about something, but their body language doesn’t seem to suggest/confirm this, we are more likely to believe that they aren’t telling us the truth. This is partly based on the correct belief that people have greater difficulty concealing their body language than their words (this is because most people are better practiced at “telling” lies/using words when engaged in deception), and this is therefore something that we should pay greater attention to. This means that we may pay more attention to non-verbal cues that we are unfortunately prone to misinterpret, and less to what is being said, which we are actually better at evaluating. This means that if we are going to be successful at detecting deceit, we need to actively educate ourselves as to what actual non-verbal cues look like, and not rely solely on our intuition and exaggerated urban myths e.g., that a person when lying will look downwards and to their right etc. This is not to say that there isn’t a degree of validity is such things, but rather that there isn’t one definitive/conclusive behavioral cue that indicates when someone is lying, as attractive as this idea may seem. In this article I want to look at three theories/ideas about detecting non-verbal cues, these are: the cognitive effort approach, the attempted behavioral control approach, and the emotional approach.

Telling a lie takes more cognitive effort than telling the truth, creating a “cognitive load”. When telling the truth, a person simply has to recall – to a varying degree of detail – actual events that have happened. When someone is engaged in deception, they have to both alter the truth, and remember what they have altered, which takes a certain degree of effort. It is important to remember that over time a person’s memory of an incident, or something they have said may be subject to change, and so an inconsistency between something recalled today, versus several months ago etc., may not indicate that the individual is engaged in deceit but rather that their memory of the event has changed/altered (something that is a natural phenomenon). This changing and monitoring facts is not the only load that the person engaged in lying is burdened by. They must also closely monitor the reactions and responses of the person they are trying to deceive, to check if their story seems credible and believable, and if not, they may have to alter and add to their account in order to be more convincing. A set of non-verbal cues that may therefore help us to detect deception is to try and identify how closely a person observes our responses. This will knock on the head the idea that those who are engaged in deceit avoid eye-contact, as a skilled liar will be closely observing our reactions to what they are saying, which involves making eye-contact. Not making eye-contact is more a signal of guilt than of deception and many people engaged in deceit don’t feel guilty about telling a lie e.g., the pedophile sports coach or priest who is planning to sexually abuse a child is likely to look a parent squarely in the eye, and tell them that their child will be perfectly safe on the sleep-away trip, etc. The additional cognitive effort engaged in creating, remembering the lie and monitoring the audiences’ responses often results in a lessening of expressive body language, such as hand and arm gestures/movement, which naturally accompany truth telling.       

We have very little self-awareness concerning our own body language, and how we look/appear when we behave in certain ways e.g., when we are angry, we don’t really know how we appear to other people etc., unless we are shown video footage of it later. Certain reactions and responses are hard to hide, such as surprise; people may try to suppress and hide the fact that they are surprised however the initial reaction to being told something unexpected is very hard to control e.g., we know what other people look like when surprised but aren’t so much aware of our own reaction. Therefore, when we are trying to appear as if we are not surprised, we are likely to copy and try and emulate, what someone who wouldn’t be surprised looks like. This means that someone engaged in deceit will often look unnatural when trying to control and suppress their behavior when being told/informed of something they didn’t expect. Other emotions and behaviors that are hard to control include anger and fear, and it is important to judge the difference between the initial reaction that a person makes and the subsequent way in which they try to control it.

The emotional approach to detecting deception, puts forward that there are three emotions associated with deceit, these are: guilt, fear and excitement, all of which lead to a degree of emotional arousal. This arousal could be subject to change during the telling of a lie e.g., a person initially may feal fearful when telling a lie because they are worried about being caught however as their audience seems to believe what they are saying they become excited, as they start to think that they will get away with it. This may result in a change/shift in body language as the person initially seems anxious and nervous but starts to grow in confidence and eventually becomes excited. Some people who are practiced in deception may even start off excited due to the power that they enjoy in “getting one over” on others. It is important to understand the context in which deception detection is attempted e.g., there are few people who won’t appear anxious or fearful to some degree when being interviewed by the police, even if they are genuinely innocent of whatever they are accused of doing – one of the reasons that it is worth having an attorney/lawyer present with you when you are involved in a police interview (the confidence that comes from professional legal representation – even if you are confident in your own understanding of the law – will help control your emotions).

When detecting deception, it is far more productive to look at a person’s emotional and behavioral responses as a whole, rather than focusing on specific cues, such as how they are sitting, or the direction of their gaze etc., as people may attempt to control certain things, like maintaining eye-contact, and if gaze aversion is the cue you are using to detect deceit, you will fail. It is important to also use verbal cues (which I have written about before) in conjunction with non-verbal cues to get a complete picture rather than focusing on one physical “tell” that you believe indicates that somebody is lying.