According to the authors, it’s actually possible to determine if someone is lying in real-time without the help of a polygraph. It’s all about employing a cognitive approach to detection.
If you suspect that someone is being deceptive, the researchers encourage a three-step process to bust them in the act.
After reviewing 23 previously conducted studies on the subject—which collectively subsumed 2,946 participants, the paper was able to support an average accuracy rate of roughly 60%.
1. Impose cognitive load
“Perform a secondary task while providing a statement, or maintain eye contact with the interviewer at all times,” the authors of the new study add.
The authors additionally suggest trying to ask a liar to recount events in question while they are performing a secondary task. Even doing something as simple as washing a dish will make relating a lie in a cohesive manner challenging.
From the report:
“Tasks designed to increase cognitive load will impair liars’ ability to provide a statement more so than that of truth-tellers. This is because lying is already a more demanding task.”
2. Encourage the liar to say more
If you’ve ever seen a criminal interrogation, you’ve likely noticed that detectives do very little talking during the first half of them. This is because the more details a liar is permitted to add to their story the greater risk they run of contradicting themselves.
Even if a contradiction is irrelevant to the main point being conveyed, its presence detracts credibility from the liar.
“It is argued that truth-tellers will be able to provide more information when encouraged to do so, since their statements will be based on real memories of an event. In contrast, liars are expected to find this task difficult, as they will be required to fabricate more detailed information on the spot,” the authors continued.
3. Ask unanticipated questions
Practiced liars will generally know how to furnish false statements with substantiating details. These will almost always be details immediately related to the fib at hand.
A good way to subvert this tactic is by presenting inquiries that have nothing to do with the statement you’re skeptical of. If a liar is taken off guard by this inquiry, this may be a sign that they’re already operating in a defensive modus.
“This technique builds on the idea that liars when given the opportunity, will prepare their answers in advance. Research suggests that prepared lies are more difficult to distinguish from truths than unprepared lies,” the authors explained.
“Liars must therefore fabricate answers to such questions on the spot, a more difficult task than simply repeating a prepared statement. It is argued that for unanticipated questions truth-tellers should provide more information and more consistent answers, in group and repeated interviewing situations compared to liars.”
There is no fool-proof way to catch someone in a lie, but there is a nearly fool-proof way to identify behaviors closely linked to deception (anxiety, tension, irregular speaking cadence.) If a speaker reliably evidences any one of them, it will be easier to buffalo them into more overt indications of deception.
“The cognitive approach to lie detection is an umbrella term for a group of active interviewing tactics designed to elicit differences between truthful and deceptive statements. Building on the idea that lying is generally more cognitively demanding than truth-telling, the cognitive approach aims to magnify this difference through strategic use of questioning,” the authors concluded.