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Four Channel Observation

by Stan B. Walters, CSP
“The Lie Guy®”

I was recently contacted by a department and asked view a videotaped interview of a subject in a homicide case.  The investigator wanted me to make an assessment of the subject’s credibility based on the interview and possibly testify regarding my findings.  There was a small catch to the request – the audio recording had failed and I was to make an analysis of just the subject’s body language deception signals.  It is not uncommon to receive requests through my office to make a behavior analysis of audio taped or video taped interviews and interrogations or even transcripts of interviews and interrogations.  I’m certainly glad to try to help any department anyway I can but there are times that I am presented with conditions that will limit my ability to make a complete credibility analysis.

The investigative interviewer should also be aware of the limitations of trying to make any credibility assessment without the benefit of observing all four channels of a subject’s communications – body language, voice content, voice quality, and micro signals.

For more than fifty years behavior analysts have noted that human communication is made up of about 65 percent body language.  Obviously that figure is not an absolute but a generalization with some people using a little less and others possibly using a larger percentage.  The father of the science of “kinesic” analysis Dr. Ray L. Birdwhitsell noted that more human communication takes place through the use of gestures, postures, position and distance than any other method.  Birdwhitsell did note however that one could make some prediction as to the nature of a conversation or interaction between parties by watching body language but he also noted that complete communication was still dependent upon all four elements.  Certainly the same can be said about the investigative interviewer’s ability to make a complete assessment of the subject’s credibility based solely upon body language cues alone.  One of the critical findings that my colleague Dr. Martha Davis and I noted in the research that we conducted was that there were numerous times that we could document that a subject was being deceptive yet there was absolutely no observable body language deception clues generated by the subject at that moment.  The cues to deception came from other any source or even sources.

Conversely, we cannot make a total analysis of a person credibility based solely of the “content” of a subject’s speech.  Speech content only comprises approximately 7 percent of human communication.  Verbal content most certainly contains the “structure” or the “logic” of a subject’s deception.  We must remember however that speech is the most diligently self-monitored portion of any individual’s communication behaviors.  Because of this constant self-censorship, verbal content cues to deception are more rare in comparison to the total volume of speech generated.  Our research as well as many other behavior analysts before us have documented that there will be many incidents of documented deception during which there will be no verbal content cues but a telltale body language cue may be generated. Such a cue and very likely the deception would be missed without the benefit of the observation of both the mediums of voice content and nonverbal cues.

Voice quality by itself holds no cues of deception.  Changes in the subject’s voice qualities of rate of speech, voice pitch and volume are quite reliable as indicators of stress, tension and anxiety. They are also certainly useful in making assessments of your subject’s current emotional state and the overall strength of the emotion being experienced. It is for this reason however that we often find voice quality cues of stress accompanying moments of deception. The value of recognizing deception using the changes in voice quality arises from the moments when the quality of the subject’s voice directly contradicts the emotional content of body language and / or the emotions articulated in voice content.

Of all forms of deception that are most difficult for anyone to accomplish are those involving emotion.  The stronger the emotion, the more difficult it is for your subject to suppress successfully.    For the same reason it will be difficult to convincingly express a typically powerful emotion that one is currently not experiencing.  Accurate analysis of the expression certainly depends on the ability of the observer to spot and identify the emotional symptoms. These failures in emotional expression are most often displayed in momentary “leaks” or what Dr. Paul Ekman refers to as “micro signals.”  Facial tics, incomplete smiles, frowns, displays of aversion, activation of the “grief muscle”, false smiles, are but a few of these telltale markers.

There are many tools available to assist the interviewer in making an assessment of any subject’s credibility.   Yet as tools they can also be subject to misuse.  We realize that human deception behavior can take on many forms and is exhibited in the various venues of human communication – nonverbal, voice content, voice quality and micro signals. Each “channel” can present the observer with critical information about the subject being observed but we will never be able to make a full and accurate analysis of the credibility of a subject’s statements without observing all four channels.  It is quite common to recognize deception only when there is a “contradiction” between the messages generated by two or more channels.  Tools for analysis of credibility will best serve the investigator when he or she recognizes symptoms of severe stress if not deception and probes those areas asking questions in depth regarding that issue and observes all four channels for more clusters of signs of credibility.

Try a Little P.A.S. in Your Interview

by Stan B. Walters, CSP
“The Lie Guy®”

We’ve discussed in class and in a past issue the four step process of Practical Kinesic Interview & Interrogation® – orientation, narration, cross examination and resolution. After the subject has presented their statement or alibi during the “narration” phase, the interviewer then takes the opportunity to address any incomplete answers or contradictions in the subject’s statement as well as obvious conflict between the statement and forensic details.  The “cross-examination” technique chosen is the one that most closely matches the subject’s personality type – emotion, sensory, logic or ego dominant.   One way to organize you thoughts for this cross-examination phase is to use a very common and very effective sales formula called P.A.S. or Problem – Agitate – Solve.  Dan Kennedy who is one of the country’s top sales professionals says that this technique “may the most reliable sales formula ever invented.”  Isn’t the interviewer doing a little selling?

The first step is to illustrate in some detail to the subject the “problem” with the facts of the case and his or her statement on the contradictions found in their statement.  For example, that despite their protestations that they were not at the scene that there are witnesses, computer logs, video tapes, credit card transactions, etc. that suggest the contrary.  Highlighting these problems can focus on the victim’s statement,  implausibility of their statements, memory lapse, etc.  Articulate in detail the “problem” as you see it and why the proof supports your position.

After you have established that there is a problem in a clear and forceful manner it’s time to get the subject “agitated” about the problem.  We do this by tapping into either their emotions about the evidence, the significance of each of the pieces of detail, the logical weight of the argument that is against their position and supports yours or the what will be the most likely public perception of the arguments that support your proof.   The idea is to force the subject to realize the futility of sustaining their argument or agree with the proof that is mounting against them.

Now that you have stated the “problem”, “agitated” the subject to the point that they are mentally wringing their hands you are going to unveil the answers to his problems. This is when the subject is desparately going to be looking for a way out of this delimma that have gotten themselves into and you are the only person who has got the “solution.” At this point you can now lay out the options the subject has available and the possible consequences and alternatives to each.  Isolate the “good” and “bad” choices that he or she has available to them and the possible outcomes for each. Be prepared to listen and to and watch your subject for verbal and nonverbal cues that indicate that an admission or confession will be imminent.

More often than not our perceptions of the difficulties and complexities of the interrogation process are often larger in our minds than they are in reality.  Sometimes a simple approach is all you need and the proven technique of “Problem – Agitate -Solve” or P.A.S. is all your need to create the foundation of a successful interrogation.