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The Language of Lying

I’m often asked about the body language tells that signal deception, and my answer often disappoints. The problem is there’s no one thing done that gives a liar away, much of the things we think we know are wrong, and we are much better liars (and much worse at detecting a lie) than we think. This article will focus on how the words we use (and avoid), and how we say them, may indicate deception. 


Before turning specifically to the verbal sounds of lying, I must note that body language is also important to consider, especially as liars are more likely to rehearse their words than their gestures, but I’ll save the tells for another day. Most people may be better off listening to liars and not looking at them if they want to detect deception, as what comes out of a liar’s mouth is often more important than their body language.

When questioning a liar, it’s useful to first get a vocal baseline, asking safe questions and attending to responses. When hearing those responses, here are the points to consider:


Liars use fewer contractions. In meeting an accusation with denial, people lengthen their statement, removing ambiguity. “I did not have sexual relations with that woman” is said, instead of “I didn’t…”  Statements that use contraction are therefore more likely to be truthful. 


Liars repeat the question. In repeating a question, the liar is buying time, so the repearting of a question (often verbatim) may suggest decpetion; this stalling tactic often following a tricky or unexpected accusation. In a similar vein, liars use interviewer’s words to answer their question. When asked, “Did you go back into the building?”, they reply, “No, I did not go back into the building.” Liars also reverse the question. When asked an accusatory question, liars may respond by attacking the interviewer by implication, twisting the question back at them: “Why are you so interested in her?”


Liars like chronology. Fictional stories are told chronologically. It’s much easier to recall and retell stories this way. When telling a true, unrehearsed story from memory, people edit, often starting with the headlines.


Liars embellish. Whilst liars are ambiguous and vague when it comes to the key moments/facts, they offer extra detail when describing non-incriminating occurrences. Often when talking about the prologue, their stories will carry the most detail.


Liars like a euphemism. Replacing events, words and phrases with softer, harmless versions allow the liar to distance themselves psychologically. It’s not only less stressful for a liar to say ‘borrow’ instead of ‘steal’, or ‘pat’ instead of ‘punch’, it’s also an opportunity to edit/change the words used by the accuser. The mafia boss who “takes someone out” doesn’t sound as bad as one who ‘kills’.  


Liars offer qualifiers. If being interviewed they might tell you how honest they are and what a fine, upstanding character others consider them to be. These qualifiers aren't always about honesty, statements like “I volunteer for my local church group” can also be made to influence how they are being seen. Liars give emphasis when arguing their case, especially where ‘honesty’ is concerned: “I swear on my kids’ lives”, “To tell you the truth”, “Honestly”.  


Liars avoid or confuse pronouns. Liars tend to leave out pronouns or shift them, removing themselves from their statements. ‘I’ and ‘me’ are removed, and pronouns are mixed: ‘he’ might become ‘we’ later in a later statement. When truthful, pronouns are emphasized, but when cognitive load becomes an issue, references to ‘self’ decease. Skipping pronouns are also common. In place of “I headed into…” they say “Headed into…”. Whilst pronouns are twisted: Q: “Did you sell them drugs at his party?” A: “You don’t sell drugs at his party.”


Liars use fillers. There are two types of fillers, sounds such as ‘erm’, ‘um’ and ‘uh’ and words/phrases ‘like’, ‘right?’, ‘you know?’ and ‘you get me?’ Fillers indicate increased cognitive load but a baseline should first be established to account for habitual fillers. It’s also true that fillers are used by truthtellers, and that the practiced lie/story could be so polished that the need for fillers is reduced or removed. The ‘sounds’ or ‘erm’, ‘um’ etc allow for thinking time and avoid silence. The words ‘you know’ and ‘right’ are confirmation seekers, attempts to prompt agreement. The word ‘like’ could indicate that what’s being said is not exactly the same as the truth, it’s only ‘like’ it. However, ‘like’ has entered common usage amongst many young people who, like, use it all the time.


Liars have a love/hate relationship with silence. When attempting deception, people tend to speak more than usual, filling silences and adding details, or they ‘no comment’ freeze. Liars, like people feeling anxious, either over-talk or clam up. Vocal pauses can occur when lies are being planned, the hesitation a sign that the person is running their answer through their mind’s filter before speaking it. Listen for changes or deviation from the baseline. 


Liars prefer to tell the truth. When they can, liars give specific denials, choosing their words with care; whilst statements like “to the best of my knowledge" cover them as the deceiver avoids lying by not making direct statements. These nonanswers are common, “I guess”.


Liars omit information. When truth telling, emotions and feelings are often expressed, spatial details relayed and different channels (sounds, smells etc) touched on. These are often overlooked when a story is being made up.  


Liars adopt a monotonous tone. To avoid imparting emphasis on certain words or allowing themselves to become emotional, liars may adopt a soft, monotonous tone. Perhaps even garbling or mumbling, hoping that what they are saying is missed or unheard. It’s a lack of conviction in the lie that is being spun.  


Liars overact and underact. Ask yourself, is this person acting suitably for the context (and compared to their baseline) or not? Liars may overact, trying too hard to convince, such as laughing loudly, or freeze, curtailing their gestures and expressions. 


Liars speak in a higher pitch. Stress can result in a higher pitched voice. Of course, stress doesn’t mean lying, but it’s a consideration. When someone attempts to deceive - and they are fearful of being caught – their voice may rise. The muscles of the throat tighten causing this change. 


Liars speak more slowly or quickly. Watch for a change in vocal speed. When anxious, people might speak quickly and liars do this when they are off-topic. If a liar can talk about something non-incriminating, a truth or small talk, they tend to chatter away letting lots of useless information obfuscate the facts. It can also help the feeling of getting it over with (reducing stress), talking quickly to get the difficult interview over and get away. And yet, when speaking more slowly than the baseline rate, it may signal a reliance upon memory. Increases in cognitive activity occur when people are trying to prevent leakage or giving themselves away. Liars are generally cautious, and the cautious speak more slowly. 


Liars over-apologise. It feels good to apologise when you’re engaged in lying. But rather than apologise for lying or doing the crime they may be being accused of, the deceiver apologises for something else, a minor misdemeanour or non-event. “I’m sorry I can’t be of more help officer”. Mini-confessions can encourage trust, it's as if one admits to something minor, it shows them as the kind of person to admit err and take responsibility.


Liars are polite or not. Politeness changes. Watch for shifts, the sudden appearance of “Sir/Mam” or a less respectful tone emerging.


When attempting to detect a truth or lie, record what is being said. There is too much to analyse in real time. It also helps to consider vocal communication alongside body language. Gestures and words interact in interesting ways where deception is concerned with asynchrony being a cue. For example, gestures and words normally occur together, but when lying, it may be that key words (lies) precede a key gesture. If they do occur at the same time, it may be that there is ambiguity, the gestures and words mismatched. In this case, the physical may be more reliable than the vocal: “Let’s get lunch” carries less weight than the accompanying ‘unconscious’ head shake.