Or, how to tell if someone is lying to you.
Much of human communication is non-verbal so we’re programmed to pick up on alternative clues to detect deception. How then, do you tell if someone is lying?
The real answer is the skilled liar will, perhaps, even be able to bypass their body’s physiological tells, though there are techniques that research scientists have developed to aid law enforcement determine who is telling the truth. I outline both here as these are great for characterisation when sketching a liar, but also instructive if you want to observe whether someone is lying to you or how you might go about catching them out.
Contradictory body language
It’s often all in the eyes. We instinctively know when someone is being genuine or not, perhaps because of their expression or confidence in delivery. Beyond this, micro-expressions can often give them game away. The slight shake of the head while answering yes, or a nod while responding in the negative are where our bodies can belie what’s coming out of our mouths. Posture shifts, gaze aversion and foot and hand movements, particularly when facing or pointing towards an exit, are all physical indicators of deception, as is looking to the person receiving the lie for their confirmation and validation.
Talking too much
People who are lying often talk too much and provide too much detail. They over-explain as if the sheer volume of information will make them seem more believable. Conversely, the liar’s explanations may be too brief, with little or no detail being offered. In this case, there’s a fear of being caught out and of overplaying their hand, so the bare minimum they can get away with seems like a better strategy. Stress factors in the voice often come into play: these may be changes in volume (getting louder) or speed (increasing in pace), or tone (becoming increasingly higher in pitch).
There may be memory loss when a liar is asked a difficult question. In actuality, they haven’t thought of or got a plausible answer and it can come across as reasonable not be able to access every little detail from a past event. Contradiction can be played to good effect here if the character you’re sketching previously had no problems with recall. Liars may also resort to hyperbole in their recollections, over-exaggerating details while underplaying others or showing more enthusiasm for some while others are quickly skipped past. There is also a curious tendency to become more formal with recall, either in using full names rather than short forms or nicknames, or in showing an importance to being grammatically correct in the retelling of the story, a sign of careful consideration to what is being said.
See no evil, hear no evil, speak no evil
Subconsciously a liar may try to cover their mouths with their whole hand or put a finger to their mouths when contemplating a question or speaking, as if to shush themselves or tell themselves to keep quiet. A liar may also go to cover their mouths but self-correct at the last minute, knowing this to be something of a sign of deceit. In this case they’ll often go to scratch their nose instead or rub an ear lobe or utilise some other form of self-comfort in the form of touching of the neck or chest, or they may cross their arms to form a barrier. The eyes may be rubbed or eye contact may be avoided at certain difficult junctures, or be made specifically to seek validation that they are being believed.
There are various questioning techniques that law enforcement have been trained in then to try to catch out the skilled deceiver who may be aware of these subconscious tells that they may have learned to control. The first, is to run a baseline reading. Here non-challenging questions are asked that are easily verifiable and where the answers are already known to all. An overall reading will be made of the subject in relation to the various tells outlined above to identify the potential deceiver at rest, in a place of comfort and safety. The next step would be to throw in a curveball of a question while the interviewee is relaxed and watch for their level of discomfort.
The second key technique is to make it harder for a liar to regurgitate their story when they do not have the ability to rely on memory and facts like a truthteller would. Here the questioner asks the subject to tell their stories in a reverse timeline. They will also be encouraged to provide more facts around time, location and recalled speech. Liars have prepared stories and it’s difficult to embellish these when it’s imperative to craft additional details on the fly.
Consider how, what is going on in the inside, psychologically with your characters, particularly unreliable narrators of the deliberately deceptive type, can be used to physically show internal machinations.
Observe body language more when watching people in conversation and watch for how that baseline reading may change when someone is asked to retell an event in a different way. Are they able to rely on memory alone?