When an interview or interrogation boils down to a session where the suspect is simply accused of lying and asked to re-tell his story, the ability to detect deception through analysis of the subject's verbal and nonverbal behavior is greatly reduced. Under this circumstance the investigator is left to evaluate information such as inconsistencies in a subject's story or unintentional verbal slip-ups. Furthermore, because of the subject's emotional state, the investigator has no way of knowing if the inconsistencies in the subject's story are coming from a confused deceptive subject or a frustrated and anxious truthful one.
In truth, we do not know what an innocent or guilty subject's behavioral responses might be during accusatory questioning because that has never been a practice of the Reid Technique -- our interviews are always conducted in a non-accusatory fashion and our interrogations, while they start out with a clear statement of involvement, quickly become a compassionate endeavor in an attempt to understand why the suspect committed the crime. During an interview we have never accused a suspect of lying to us. Similarly, during an interrogation we would never admonish a subject for lying to us and make him go through his account again. Perhaps these techniques do result in confessions and are used successfully by other investigators. However, they do not represent techniques advocated or used by John E. Reid and Associates and, therefore, we do not have any guidelines to offer with respect to how a guilty or innocent subject may respond to them.
A recent laboratory study conducted by Kassin and Fong support our teachings in this area.(1) Video-taped interviews of students who were assigned either guilty or innocent roles in committing a mock crime were analyzed by student observers. These interviews consisted of eliciting an initial statement from the student but then the investigator became angry and said, "Dammit, stop lying to me! We caught you cold. Now tell the truth." The subject was then told to restate his alibi. The average interview lasted less than five minutes.
Half of the student observers who reviewed the video-taped interviews were "untrained" and relied on common sense (inconsistencies in accounts, verbal slip-ups, general nervousness) to formulate opinions of the subject's truthfulness and the other half were "trained" in behavior analysis by watching a 30 minute video describing some of the behavior symptoms used to evaluate a subject during a non-accusatory interview. The study produced two predictable findings: first, neither the trained nor untrained student observers were able to identify truthful or deceptive subjects above chance levels. Second, the trained students, who relied upon behavior symptoms elicited during a non-accusatory interview, performed statistically poorer than the untrained students.
In conclusion, a subject's behavior during the course of an interview or interrogation can be influenced by many factors such as the environment in which the behavior was elicited, the subject's intelligence or age, the subject's emotional state and, of course, the investigator's demeanor. Each of these variables need to be considered when deciding how much weight to afford behavioral observations. To the extent possible, the investigator should eliminate or minimize the effects of these variables. For example, an investigator should try to conduct an interview in an environment free from outside or internal distractions, a subject who appears angry or upset should be calmed down before an attempt is made to elicit specific behaviors of truth or deception. Most certainly, the investigator should not do or say anything during an interview that would place the suspect on the defensive or cause unnecessary anxiety or apprehension.
1. Kassin, S. & Fong, C. ""I'm Innocent!": Effects of Training on Judgments of Truth and Deception in the Interrogation Room," Law and Human Behavior, Vol. 23, No. 5, 1999.