To catch a liar

Researchers at the University of San Francisco did a study to determine if particular groups of people were better able to detect a lie than others. Out of a selection of various law-enforcement and intelligence officers, lawyers, psychiatrists, and many others, only one group showed a better-than-random ability to detect a liar: the Secret Service. Why? Among their speculations:

The members of the Forensic Services Division of the Secret Service whom we tested spend part of their time interrogating people who threaten to harm government officials. Secret Service officials told us that most of these people are telling the truth when they claim that their threat was braggadocio, not serious. It is only the rare individual who is lying in his or her denial and actually intends to carry out such a threat. Members of the criminal justice community told an opposite story; they believe that everyone lies to them.

(Emphasis mine).

So in order to catch a liar, you have to be willing to believe that most people are telling the truth.

(Thanks to erudito for the link).

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  1. Note…

    well.. that’s a bit of a stretch for a conclusion.. what would be more accurate is that
    “in order to catch a liar, you have to have a lot of experience learning how people tell the truth, and this then gives you a stronger chance of being able to determine when people lie.. “

    I say this.. because we don’t have any information here on how accurate the beliefs of the criminal justice community is.. i.e. do people lie to them consistently? I know on every cop drama you watch–and in most of the documentaries about various trials–like the laci peterson case–you find individuals lying all the time…

    Perhaps the conclusion that I would reach would be: If you are around people–the majority of which lie all the time–then you lose your ability to believe that people do tell the truth–and this impairs your overall skill to determine truth and lies…

    1. Re: Note…

      That was the conclusion that the article reached as well. But I had the same question as you, which they ignored – are the law-enforcement officer’s beliefs about the people interview justified, or just the result of an institutional bias?

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