CRIME: The perfect, 95%+ accurate witness interrogation technique
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The researchers conducted three studies based on sets of participants who were asked to play a trivia game. Unbeknownst to the participants, a confederate was placed with them offering an incentive and opportunity to cheat at the game, since cash prizes were involved. In the first experiment 12% of the subjects cheated; in the second experiment 44.9% cheated.
An expert using Truth Default Theory interrogated participants in the first study, this expert was 100% accurate (33 of 33) in determining who had cheated and who had not. That kind of accuracy has 100 million to one odds. The second group of participants were then interviewed by five US federal agents with substantial polygraph and interrogation expertise. Using a more flexible and free approach (interviews lasted from three minutes to 17 minutes), these experts were able to accurately detect whether or not a participant cheated in 87 of 89 interviews (97.8%). In the third study, non-experts were shown taped interrogations of the experts from the previous two experiments. These non-experts were able to determine deception at a greater-than-chance rate -- 79.1% (experiment 1), and 93.6% (experiment 2).
Previous studies with "experts" usually used passive deception detection where they watched videotapes. In the few studies where experts were allowed to question potential liars, either they had to follow questions scripted by researchers (this study had no scripts) or confession seeking was precluded. Previous studies found that accuracy was near chance -- just above 50%.
"This research suggests that effective questioning is critical to deception detection," Levine said. "Asking bad questions can actually make people worse than chance at lie detection, and you can make honest people appear guilty. But, fairly minor changes in the questions can really improve accuracy, even in brief interviews. This has huge implications for intelligence and law enforcement."
Truth Default Theory
The researcher's findings have led to a new theory, Truth Default Theory. Levine's idea is that when humans communicate with other humans, they tend to operate on a default presumption that what the other person says is basically honest.
"The presumption of honesty is highly adaptive. It enables efficient communication, and this presumption of honesty makes sense because most communication is honest most of the time. However, the presumption of honesty makes humans vulnerable to occasional deceit" Levine said. "There are, of course, times and situations when people abandon this presumption of honesty, and the theory describes when people are expected to suspect a lie or conclude that a lies was told, and the conditions under which people make truth and lie judgments correctly and incorrectly."
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Story Source: Materials provided by International Communication Association. Timothy Roland Levine, David Daniel Clare, J. Pete Blair, Steve McCornack, Kelly Morrison and Hee Sun Park. Expertise in Deception Detection Involves Actively Prompting Diagnostic Information Rather Than Passive Behavioral Observation. Human Communication Research, 2014