Over the years researchers in the academic community have conducted a number of research studies on an investigator's ability to detect deception; more specifically these studies have attempted to determine if the nonverbal and verbal behavior symptoms that are used by practitioners to help them assess the credibility of suspects are, in fact, reliable indicators of truth or deception.

In the overwhelming majority of these studies the results have been rather dismal, essentially suggesting that nonverbal behaviors (and to a lesser extent verbal cues) offer little value in assessing a suspect's credibility. (Bond and De Paulo," Accuracy of deception judgments", Personality and Social Psychology Review, 2006.)

In light of these results, why would field practitioners place any reliance on the behavior displayed by a suspect during an investigative interview for indications of truth or deception? One reason is that the vast majority of research studies do not mirror the context and structure of real life interviews that are conducted in the field, and, as a result, have very little relevancy to the real world.