Twenty-two people in a castle, Claudia Winkleman hamming it up like crazy, a number of silly challenges, a chunk of money sitting at the centre, almost glowing, and human nature laid bare. To try to pick apart exactly what makes The Traitors so compelling would be to miss the point, like trying to analyse the ingredients in a Krispy Kreme doughnut. As enjoyable as it is, though, the show gets more infuriating with each episode. I don’t want to point fingers, still less give spoilers, so let’s keep this broad: why are they (the Faithful) all so stupid? Why can’t they tell when they are being lied to? It’s so obvious! I asked three experts how to spot a lie – and why most people can’t. First, Dr Linda Papadopoulos, a psychologist, author and broadcaster, whom people of a certain vintage may remember as the standout discovery of the first season of Big Brother. Reality TV was in its infancy, so watching ordinary people interact under a microscope was fascinating in itself, but Papadopoulos, the show’s resident psychologist, added an almost superhuman level of insight into the contestants’ feelings; she was like a mind-reader. Second, Joe Navarro is the author of What Every Body Is Saying, insights into non-verbal cues and tells gleaned from his career as an FBI agent. Gabrielle Stewart, the third, is a retired insurance investigator who works as a fraud consultant for the industry. This trio don’t always agree but, seriously, you wouldn’t want to lie to any of them. Here are their 10 tips for spotting a liar. Watch for self-soothing gestures “The problem with the myth of detecting deception is that since the groundbreaking work of Paul Ekman [a psychologist whose visual test, Pictures of Facial Affect, was published in 1976] and all the researchers that came after him, we know that humans are no better than chance at detecting deception,” says Navarro. But that doesn’t mean you can’t read anything into people’s expressions and behaviours. “What the human body does – and it does it exquisitely – is display psychological discomfort in real time,” he says. “King Charles – he’s always playing with his cufflinks. This is how he deals with social anxiety. Prince Harry – he’s always buttoning the button that’s already buttoned – another comforting behaviour.” Facial touching is known as a pacifier – a way to soothe yourself under stress. “Right now, you are covering your suprasternal notch,” says Navarro as our video call starts. Protecting my neck, in other words, “which is because there’s a man right in front of you”. That makes me chortle, because I love men. But he is right in the sense that I have always keenly felt the jeopardy of the first few seconds of an interview – if you make a mess of that, the whole thing is ruined. So, there is the first principle: everything someone does with their hands and their face says something. Now, you have to figure out what. Probe areas where you detect psychological discomfort Navarro recalls a search for a fugitive during his FBI days. Interviewing the man’s mother, he asked if she had seen her son. She said no and was plainly nervous, but there was no way to connect the anxiety to the answer; she could have been telling the truth and simply been unsettled by the appearance of two FBI agents on her doorstep. He changed tack and asked if it was possible that her son was sneaking in to the house while she was at work. “She said: ‘No, that’s not possible at all,’” displaying a nervous tell – covering her neck, in this instance. “But there was no reason for that, right? All she had to say was: ‘I don’t know.’” So the non-verbal show of nerves combined with the illogical answer hinted at deception. Sure enough, the man was in the house. Don’t take obvious gestures at face value Some striking non-verbal tells are rooted in archaic human self‑preservation. We cover our mouths when we see something shocking or horrible, because “it prevents the casting of our scent, which predators can pick up on,” Navarro says. The problem is that the more obvious the gesture, the easier it is to plan for and mimic. So, every time they vote out an innocent player on The Traitors, all the Faithful cover their mouths in horror, but so do the Traitors. Big, set-piece events, where everyone is making the same face or gesture, probably won’t tell you very much. Look for mismatch Papadopoulos picks up on the space between the non-verbal and the verbal – the incongruity between words and gestures: “You’re nodding, but saying no.” Stewart listens for acoustic variance in speech, where pitch and tone change. Lying people will pad a story with elements of truth, which is probably smart, except that, when they come to the falsehoods, “they speed up and speak at a higher pitch”, says Stewart. “The voice is saying: ‘I’m in cognitive overload.’” Learn to receive, not transmit “The ability to actively listen, which is what psychologists do, is surprisingly rare. A lot of people are thinking of what they’re going to say next, rather than listening,” Papadopoulos says. We also forget how much of ourselves we bring to the interaction; if we are stressed or anxious, it’s harder to detect or decode stress in others. Papadopoulos describes falling for a scam when she was in the middle of a family crisis: “I write about these things – I know my stuff – but, in that moment, I was duped. If I was on my game, that would have been much less likely. That’s the whole basis of psychology: we think through our emotions and that moderates the quality of our thinking.” Don’t ignore the impact your tone is having on the conversation (memo to The Traitors’ Diane): “If you come across as accusatory, that affects how people react,” Navarro says. “I never did that, as it puts people on the defence and it begins to mask behaviours that I need to observe.” Don’t jump to conclusions, either. Classic ways to spot a liar – such as vagueness, or buying time, Papadopoulos says – might mean something completely different. “It might just mean they weren’t really listening,” she says. If you decide too quickly that you have uncovered deception, it gates off other possible explanations. Get them to tell their side of the story Stewart, who did her insurance investigation work by phone, says: “The structure of the account is key. You wouldn’t necessarily do this in person when you’re speaking to somebody, but any story will have a beginning, a middle and an end. It’s normally 30% buildup, 40% content, 30% afterthoughts and reflections. An untruthful account won’t stick to that structure, because they don’t really want to tell you that 40%. The most common structure of a lie will be 80% buildup, then they’ll tell you what happened really, really quickly, then they’ll want to get it over with. “I would record an event using timelines and bullet points on landscape paper, then draw a line where I believe I’ve gone from beginning to middle to end. Almost every fraudulent account will have a very long beginning, bugger-all middle and bugger-all end.” Memory-blamers are a flag: when something significant happens, it’s very unusual to forget it. Even if it has been misremembered or misperceived, there won’t be a big hole in the memory where that detail should be. Listen for tenses and dissociation “We use completely different language when we’re telling lies,” says Stewart. “A really famous example is President Nixon. He was asked straight out: ‘Did you know about Watergate?’ and his answer was: ‘The president would do no such thing.’ “First, he’s got disociation, which is very common. In an untruthful account, there’s a lack of ‘I’ and ‘my’, because we want to push the lie away from ourselves. Then, he’s slipped tenses.” A truthful person whose car has been stolen, for example, will say: “I left it here, came back an hour later and it was gone.” An untruthful account might slip into the present continuous: “I’m walking down the path and I’m looking for my car, thinking …” Be alive to odd noises or random words Stewart talks about “emotional leakage”. A liar might randomly start laughing, but it won’t sound like mirth. Time-filling sounds are common. “It’s an additional cognitive load, saying untruthful things,” she says. “It’s like patting your head and rubbing your stomach at the same time. So, they’ll be on high alert and they can’t bear silence. You’ll hear coughing, or strings of words that don’t need to be said.” Allied to this is non-committal language, or “linguistic hedging” – words such as “probably” and “possibly”. “They’re like disclaimers: ‘I don’t want to commit myself with this language.’” Ask character questions In the 80s, my dad, who was a prison psychologist, devised some recruitment tests for the police that were designed to establish whether candidates were honest. One of the progressions was: “Are you married? Have you ever had an affair? Have you ever thought about having an affair?” If you answered yes to the first, it didn’t matter what you said to the second, as long as you didn’t answer no to the third, because everyone’s thought about it. To apply this to The Traitors, a player could ask of another: “Do you find Zack annoying?” If they say no, it doesn’t prove that they are a Traitor, but they are certainly the kind of person who lies. Ask yourself: are you looking through the right end of the telescope? Every one of these clues – verbal, non-verbal and in between – relies on something: the liar’s discomfort. Not everyone will feel discomfited by mendacity; some people will enjoy it. “We know that 1% of any given population – here in America it may be way more – are psychopaths,” says Navarro. “These people can lie all day long. There are structures in their prefrontal cortex that just don’t function.” Added to that, “4% of the population is antisocial; these are people who live by criminal activity”, he says. Even if they weren’t born to deceive, they will be habituated to it. Many people have to lie for their jobs. Navarro mentions spies and doctors, but makes the broader point that we all use lying “as a tool of social survival”. Inevitably, some of us will end up quite good at it. But what are we trying to survive? We want to remain members of the group and we fear expulsion. In a culture where lying is prized – politics, The Traitors – the act of lying might make you come across as more confident, rather than less. So, if you cross-referenced the verbal and non-verbal cues, then reverse-engineered the tests to become reasonably good at identifying an honest nervous person, you could figure out who was lying by a process of elimination; even if they were psychopathically good at it, that wouldn’t matter. In The Traitors – and in life – what will undo you is letting yourself become certain on the basis of too little information or ambiguous evidence. “I looked at 261 DNA exonerations in the US,” Navarro says. “All the police officers thought that they could detect deception, but not one of them could detect the truth. In fact, none of the men were guilty.”