With more than 100 scholarly papers to her name, Bella DePaulo, visiting professor of psychology at the University of California, Santa Barbara, is a preeminent authority on lying and deceit behavior. In her book, The Hows and Whys of Lies, the Harvard University–trained researcher provides a thorough overview of the results of hundreds of lying and deceit behavior studies. Here is a summary of her major conclusions.
- A review of 253 samples in which truth detectors were shown equal numbers of truths and lies found that the accuracy rate at detecting lying and deceit behavior was only 53%. This result is extremely similar to the 54% lie detection accuracy rate found by Dr. Maria Hartwig and Dr. Charles F. Bond, Jr. in their paper “Why Do Lie Catchers Fail: A Lens Model Meta-Analysis of Human Lie Judgments.”
- Ambivalence on the part of someone being questioned seems to be an especially strong indicator of lying or deceit. Again, this result is similar to that found by Hartwig and Bond.
- People, when listening, often properly identify a lie, but when asked to commit to an assessment they do not listen to their intuition, thus nullifying the accurate assessment (Hurd and Noller 1988).
- Additionally, truth detectors report feeling more confident when hearing the truth than they do when hearing a lie.
- When talking for long periods of time, liars have a higher pitch than those who are telling the truth.
- Liars take a longer amount of time to respond to a question when asked.
- In general, liars are less talkative than truth tellers.
- If liars have had time to prepare their answers, they respond to questions faster than truth tellers.
- If liars have had less time to prepare their answers, they respond to questions slower than truth tellers.
Here is an overview of behavioral cues along with their correlations to the presence of lying behavior. Due to space constraints not all of the behaviors listed can be explained. DePaulo’s book contains further details.
|2||Pitch (when motivated)||0.59|
|3||Verbal & vocal immediacy (impressions)||−0.55|
|5||Admitted lack of memory||−0.42|
|8||Related external associations||−0.35|
|12||Rate of speaking||0.32|
|13||Verbal immediacy (all categories)||−0.31|
|14||Verbal & vocal uncertainty||0.30|
|17||Nervous, tense (overall)||0.27|
|21||Foot or leg movements||−0.24|
|23||Verbal & vocal involvement||−0.21|
|23||Word & phrase repetition||0.21|