[News] Signs investigators rely on in identifying perpetrators and liars

[rlex]

 

You cannot reveal other people's lies just by looking at them, but psychologists have recently focused their attention on other methods that may be more effective in detecting lies.

Police officers assumed that Marty Tancliffe appeared too calm after discovering his mother had been stabbed to death and his father had been beaten to death with a club in the family's spacious home on Long Island, USA. Although he denied the charges against him, authorities did not believe him, and he spent 17 years in prison.

In another case, investigators assumed that 16-year-old Geoffrey Skovich appeared more distressed than usual and was suspiciously eager to help investigators, after his high school classmate was found suffocated. The court found that he was a liar and he spent nearly 16 years in prison.

In the first case, the young man was not bothered enough, and in the second case he was more disturbed than usual. How can these contradictory feelings expose the falsehood of the accused in both cases?

Maria Hartwig, a psychologist and researcher in deception techniques at the John Jay College of Criminal Justice at City University in New York, says the defendants, who were later acquitted, were victims of a common misconception that it is possible to tell whether a person is a liar or true by looking at the way he is behaving. . This is why people across cultures believe that behaviors such as avoiding eye contact, nervous movements and stuttering, expose the deceiver.

But after decades of searching, researchers have found little evidence to support this belief. "One of the problems that lie researchers face is that all people think they are polygraph experts," Hartwig says. "But errors in lie detector have huge implications for society and people who are victims of wrong opinions and judgments."

This overconfidence in indications of falsehood has often misled justice, and Tankliffe and Discovic are well aware of its consequences.

Psychologists have realized how difficult it can be to detect a lie. In 2003, Bella DePaolo, a psychologist at the University of California, Santa Barbara, and her colleagues combined 116 trials that compared people's behaviors when they believe the words and when they create gossip. The studies evaluated 102 potential nonverbal indicators of lying, such as avoiding eye contact, blinking quickly, having a high pitched voice, shaking the shoulders to express apathy or ignorance, and changing the position and movements of the head, hands, arms and legs.

But it has not been proven that any of these behaviors were indicative of lying, although few of them were associated in some cases with lying, such as dilated pupils and very slight elevation, which the human ear does not perceive, in the tone of the voice