Think about your favorite criminal justice TV show, when the detective thinks the suspect is lying and wants to incriminate him, what does he do? Gives him a lie detector test! The lie detector test, also known as the polygraph test, has been a socially acceptable way of detecting lies in the 20th century. But is it really valid? The polygraph test is based off of lie detection tendencies such as the Pinocchio response; a physiological/behavior indicator of lying. Statistically it does better than chance but yields a high rate of false positives. This is due to the fact that the polygraph test doesn't specifically detect lies, it detects arousal. The suspect could be experiencing arousal because he's nervous of being wrongly convicted of the crime, and this would create what looks like a "lie" on the test. This happens more often then not. Well if the polygraph test isn't as reliable as expected, is what about human instinct? Most of us are pretty confident of our skills at detecting lies. Although we are also better than chance most of us only achieve a 55% accuracy rate and it's shown that there's little to no correlation between our confidence of detecting lies and our abilities. Both personal instinct and the scientific route of the polygraph test are better than just flipping a coin, but they are nothing to fully rely on.
Liar, Liar, Pants on Fire
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