For years, the theory has gained popularity in psychology that, when it comes to detecting signs that the person who is talking to us is lying, it is good to look at the expressions on their face. That is, taking into account the non-verbal language that is expressed through facial gestures is necessary to know if someone is telling the truth or not.
The idea is that there are some signals, called facial microexpressionswhich appear in different points of the face and are so discreet, automatic and involuntary that reveal aspects about the person’s true intentions and motivations
However, a recent study calls this idea into question by pointing out that when it comes to detecting lies, the less you can see the other person’s face, the better. That is Stopping paying attention to these visual cues can be helpful in getting closer to the truth
This investigation was promoted by political issues: there are proposals to not allow witnesses in trials to wear clothing associated with the Muslim religion such as the niqab, which covers the entire head and leaves only the woman’s eyes exposed.
That is, we wanted to see to what extent the reasons for prohibiting this were reasonable and based on objective facts related to the way in which we can detect lies. To do this, a series of research teams from the University of Ontario and the University of Amsterdam coordinated their efforts to examine this topic in the laboratory.
The study had two types of experiments in which a series of volunteers had to say whether several women who acted as witnesses were telling the truth in a mock trial. To make it more realistic, each of the witnesses was shown a video showing a person stealing a bag or not, so that each of them saw only one of the two versions of what could happen: either it had been stolen , or not. Additionally, they were told they had to testify about the behavior they had seen and half of them were made to lie about what happened.
During questioning at the trial, some of the witnesses wore a hijab, which covers parts of the head but leaves the face exposed; others wore the aforementioned niqab that only reveals the eyes of the wearer, and others wore clothing that did not cover the head. These trials were filmed and then shown to students in Canada, the United Kingdom and the Netherlands. They had to find out who was lying and who was telling the truth
The results: the less you see, the better to know who is lying
The results, published in the journal Law and Human Behavior, were surprising. Curiously, The students were more skilled at detecting lies when they had to judge women with almost their entire face covered In other words, it was easier to be right about what women thought when they wore the hijab and, to a lesser extent, the niqab. Women who did not have any part of their heads covered were always “uncovered” to a lesser degree than the others. In fact, it happened with them that they were recognized as witnesses who lied by pure luck, since the success rate was not significantly different from 50%.
Not only did this go against the logic that we make more accurate judgments the more information we have, but it also indicated that negative stereotypes about Muslim women did not lead to more less favorable judgments about them.
Possible explanations for this phenomenon
What do these results mean? One way to interpret them is to assume that The non-verbal signals that we take into account (even unconsciously) when judging the veracity of what we hear distract us more than anything else causing us to reach false conclusions by relying on irrelevant information.
Therefore, the barriers that cover facial expressions mean that we are forced to direct our attention to more reliable and relevant sources of information, such as the tone of voice, the frequency with which grammatical errors are made, the tremor of the voice, etc. . In fact, some of the students directly placed themselves in a position in which they could not see the screen on which the video was shown when it was their turn to detect the possible lies of the veiled women, so as not to be distracted.
