This new method is simple and effective for detecting lies

Detecting lies could become easier thanks to a new approach developed by researchers at the Leugenlab of the University of Amsterdam, in collaboration with the Universities of Maastricht and Tilburg.


Forget body language and message conviction: just focus on the richness and detail of the story being told. This method relies on a simple yet effective observation: liars, though they may invent details, increase their risk of being caught.

Security personnel are trained to spot up to 92 signs of lying. For Bruno Verschuere, an associate professor in forensic psychology, this is an impossible task. According to him, it is unrealistic to ask someone to evaluate that many signs in such a short time and combine them for an accurate judgment. Moreover, we tend to instinctively believe people who seem innocent, which benefits liars.

Leugenlab proposes a new method of detecting lies based on a single signal: the level of detail in the story. Honest people can provide a rich description because they have truly experienced the event. This counterintuitive method proves to be very effective.

To verify the reliability of this approach, researchers conducted a series of lab experiments. A group of students was divided into two: the guilty and the innocent. The guilty had to steal a copy of an exam from a locker, while the innocent were simply spending time on campus. Then, all participants had to declare they had spent half an hour on campus.


In nine studies involving 1,445 people tasked with discovering who was lying and who was telling the truth, these individuals assessed the accuracy of handwritten statements, video transcripts, video interviews, or live interviews of the students. When allowed to use all possible signals, they struggled to distinguish the guilty from the innocent. However, by focusing solely on the amount of detail (place, person, time, location), they consistently succeeded in discerning lies from truths.

This research has significant implications for the methods of lie detection used by law enforcement and security agents. By simplifying the process and focusing on a single reliable signal, it becomes easier to train personnel to detect lies effectively.

The research is published in the journal Nature Human Behaviour.