Here’s an unsettling fact to think about: most people really suck at guessing whether they are being lied to. This is according to a new piece of research from the University of Edinburgh in Scotland, published this week in the Journal Of Cognition.

There are many tell-tale signs that someone is lying, many of which we pick up subconsciously, such as shifting eyes, changes in speech rate, awkward hesitations, etc. However, this new study highlights how the verbal and physical signs of lying are actually considerably harder to detect than people believe, and those "tells" we think we can detect can't really be trusted. 

“The findings suggest that we have strong preconceptions about the behavior associated with lying, which we act on almost instinctively when listening to others,” Martin Corley, School of Philosophy, Psychology and Language Science, said in a statement. “However, we don't necessarily produce these cues when we’re lying, perhaps because we try to suppress them.”

They reached this conclusion by asking a group of participants (just 24 people in total) to take part in an experiment involving a computer game where they hunted for treasure with another player. As a key caveat, people were allowed to lie, trick, and deceive their partner.

Each turn, a player chooses whether to correctly name the location of some treasure or to lie, then the other player guesses where they think the treasure is hidden based on their partner's statement. During this showdown, researchers looked out for 19 different cues from the players' body language and verbal nuances that hinted they were telling fibs. They also kept tabs on which cues listeners interpret as evidence that a statement is false.

People appeared to decide whether someone was lying or telling the truth within just a few hundred milliseconds of encountering a cue. However, weirdly, players often muddled up the cues and made the wrong associations. For example, it appears that cues associated with lying were more likely to be used if the speaker is telling the truth.

So, we may subconsciously pick up on certain "lying" cues but when these cues aren't evident we don't consider they might be being suppressed. Also, it appears people who are not lying are just as likely to either unconsciously, or because they are aware them, perform the tells we associate with lying, which means these cues are unreliable for detecting if someone isn't telling the truth. 

In sum, body language that suggests people are lying is not as straightforward as you might assume, and we're actually surprisingly bad at accurately discerning whether somebody is tricking us or being sincere.

If there is any positive news from the study it’s that people actually told the truth most of the time. Equally, people thought others were being truthful in most instances. So there, perhaps we can trust each other after all.