People lie. From little white lies to the lies that scar the world, lying is a fact of life. It’s also a fact that most people are honest but from a glance, the liars (especially the masterful ones) and the truth tellers can be difficult to tell apart. Now there’s research that can guide us through. 

A popular misconception about lying is that there are verbal or nonverbal behaviours that are a dead giveaway that you’re being lied to. The disappointing news is that there aren’t.

Previous research has found that both experts and non-experts have a 50/50 chance at detecting a lie.

So – unless the nonverbal cue involves something less subtle, like a written admission tied to a balloon and passed to you mid-fib, your odds at deception detection are no better than flipping a coin.

Enter the scientists.

Researchers have found a way to increase our odds at detecting deception and it has little to do with nonverbal cues. Rather, it’s based on the fact that lying is hard work and to be successful at the con, liars have to be working on several things at once, all of which increase the cognitive load and lean hard on mental resources:

• They have to be sure about their story, making sure nothing slips to gives them away. Everything they say has to line up. This is hard work when there’s nothing concrete (like, say, the truth) to anchor to.
• They have to memorise their story and act as though it’s true. A decent lie needs the relevant emotion to make it believable. Contriving emotion is no easy task, though of course there’ll always be those who are masterful.
• They have to constantly assess whether the listener is ‘buying’ their story and make adjustments where necessary – more emotion, less emotion or fatten the story with extra detail.
• They have to continuously refer to their memory to make sure the story they’re telling now is the same as the version they told before.

Clearly, lying is hard work, drawing on a lot more mental resources than telling the truth. To lie is to perform and to perform takes effort, not the least of which is remembering the script and delivering a knockout performance.

Using this observation, the experts in the field have come up with ways to expose the liars in our midst by depleting their much needed mental resources, to the point where liars are unable to keep up the act:

1. Ask questions from the assumption of guilt.

   Ask questions based on a presumption of guilt, rather than innocence, and actively interrupt denials. A recent study published in Human Communication Research demonstrated that this type of questioning could uncover a lie 97.8% of the time. This is compared to the 50% strike rate when this isn’t used.

   (Be careful though – if you’re going to do this, make sure you have good reason to suspect you’re being lied to. Understandably treating honest people as though they’re liars is likely to make them bristle.)

2. Ask open then closed questions.

   . Closed questions can be answered with a quick ‘yes’ or ‘no’. People who are telling the truth want all the facts to be out there so in response to a closed question, they’ll often give more than a one word answer. Liars, on the other hand, will say less for fear of revealing their deception. For them, a ‘yes’ or a ‘no’ will be plenty.

    

3. Ask about the story in reverse.

   Rather than starting at the beginning and asking what came next, start at the end and ask what came before. It’s hard to tell a story in reverse at the best of times but when the facts are made up, it’s even harder. If the story you’re being told is a fib, you’ll soon see the slipping and sliding.

4. Ask unexpected questions (about unexpected detail). 

   Liars are as sensitive to the cliches (‘I don’t remember’/ ‘I don’t know’) as the rest of us so they’ll try to give reasonable answers. Often they’ll have worked out the more significant details in advance but the smaller ones won’t have been given a thought. Ask about those. If you suspect that ‘I was at a work dinner’ is a lie, ask: Who did you sit near? What did they eat? What did you talk about? Who was still there when you left? What did you eat? Where was the table? How many empty tables were there? The detail you ask about depends on the lie, but ask about smells, colours, cost etc. Ask the same questions more than once but in a different way.

5. Maintain eye contact.

   Okay. This is kind of non-verbal but when used with the other tips, it will give your internal lie detector a boost. When people lie, they have to constantly draw on their memory to make sure what they’re saying lines up with what they’ve said before. The story has to be exactly the same as every version that came before it. This is hard and best done without the distraction of pesky humans who are trying to get to the truth. When somebody is lying, their gaze will often turn to motionless things that won’t distract them while they set to work trying to remember their script. Keeping eye contact makes this harder.  

Most people are honest. I really believe that. But there a few things nothing worse than the feeling you get when you think you’re being played. These strategies will help weed out the fakers, but use them wisely. We all know trust is the scaffold of any relationship and there’ll be damage to repair whenever the scaffold is given a shake – either from lying or from one too many false accusations of lying. Of course, if the scaffolding was shoddy to begin with, then shake away …