Most defense experts who testify on the issue of false confessions state that law enforcement investigators interrogate people whom they believe are lying to them based on the behavior that they displayed during the initial investigative interview. The experts go on to say that the majority of studies show that there are no reliable behavioral indicators of truth and deception. Consequently, investigators oftentimes interrogate people who are actually innocent, which then leads to false confessions.

In most detection of deception research there appears to be a fundamental lack of understanding of how verbal and nonverbal behaviors exhibited by a subject during an interview are evaluated by practitioners in real life settings. Most academics conducting research seem to work on the underlying presumption that there is a behavior - verbal and/or nonverbal - that is unique to deception. There is not. Any attempt to evaluate a subject's behavior for indications of deception must be considered in the context of the situation and the potential influence of a variety of factors. To do otherwise would be a fruitless endeavor.

Here are a few of the principles of behavior symptom analysis as practiced in the field that academic researchers fail to consider.

There are no unique behaviors associated with truthfulness or deception. The behavioral observations an investigator makes of a suspect do not specifically correlate to truth or deception. Rather, they reflect the subject's internal emotional state, cognitive processes, and internal physiological arousal experienced during a response. The emotional states most often associated with deception are fear, anger, embarrassment, indignation, or hope (duping). The cognitive processes may reveal concern, helpfulness, and confidence versus offering an unrealistic explanation for the crime, being defensive, or being overly polite. There are also internal physiological responses that cause external behavioral responses such as a dry throat, skin blanching, pupillary dilation, or blushing. Observed in isolation, certainly none of these behaviors should cause an investigator to conclude that a subject is telling the truth or lying.