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Interrogation Techniques

Intuitive versus Analytical Diagnosis of Credibility

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

Historically human beings are very bad at spotting deception failing on average 50% or more the time to identify lies. Unfortunately, investigative interviewers and  professionals in many other disciplines also have the same poor performance based on numerous research studies.  One of the major contributing factors is that most of us make our assessments about whether a person is being truthful or deceptive based on our “gut feelings” and other undefined symptoms.  Such intuitive assessments have always proven themselves to be inconsistent and unreliable.  When an investigative interviewer focuses their analysis on more reliable documented verbal and nonverbal cues, their accuracy dramatically improves.

An “intuitive” analysis of a subject frequently is characterized by comments such as “I think he’s lying” or “I know he’s hiding something.”   When you ask the observer what specific behaviors make them believe the person is deceptive you often get answers such as “I can tell,” “You just know” and they fail to identify any reliable cues. When they do cite verbal or nonverbal cues those that are mentioned as deception markers are more often than not are just signs of stress or incriminating stress cues and fail to isolate lies.

A reliable analytical diagnosis of behavior focuses on specific questions or issues and clearly defined behavior responses by the subject.  These analyses are characterized by comments including terms such as “clusters”, “timing”, “consistent”, “change” and “constant.”  In these cases the interviewer – observer can be very specific about a subject’s deception and can name the particular behaviors. The behaviors mentioned will be cues identified as “denial”, “aversion”, “negation”, “contradiction”, “unclear thought line” or “performance.”

The danger of making an “intuitive” diagnosis is that they are subject to “pre-conceptions” by the interviewer that more often than not results in gross misdiagnosis.  As we’ve discussed in the past the existence of pre-conception on behalf of the interviewer is also most often results in contamination of the interview further compounding the error of the credibility assessment.   The end result of such a flawed analysis can be wasted time, investigative effort and resources and at worst a case subject to crushing attacks that can be made in defense of the subject in trial and disciplinary proceedings.  An analytical diagnosis requires a lot more effort by the interviewer.  The observer will force themselves to resist making blanket statements about their subject’s lack of honesty without specific behaviors they have identified to support their conclusions.  Cases made with such extensive micro-analysis typically contain better quality information and often other forensic sources that provide confirmation of the subject’s remarks.  These cases are also more likely to survive any challenge of prejudice, flawed analysis, contamination and some cases even false confession.  On what basis are you deciding the subject is being deceptive – your ‘gut feelings’ or reliable behavioral cues that you can cite on a point-to-point basis? Don’t just tell me your subject is lying – tell me what he or she is lying about and the specific behaviors that have led you to that conclusion.

Over Prepared Interviews

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

There is nothing unusual at all about any investigative interviewer preparing extensively for an upcoming interview. There is really no situation that I can think of that I had too much information on hand when I went into the room. The danger may be however that we can become too obsessed with the preparation at the expense of being spontaneous and flexible when we finally get into the room.   Certainly “turning unknowns into knowns”  is a good strategy for reducing our tension as the interviewer and we often mentally practice what we are going to say and anticipate any possible surprises and build backup plans to deal with such surprises.  Over preparation however can paralyze the interview and information recovery.

Are your “scripting” your interviews?  One telltale sign of over preparation is literally scripting the interview questions.  In some cases writing out the questions in advance and even sequencing the questions in the order they may be asked.  The danger here is that the interviewer becomes so “fixated” on completing the list of questions that they fail to follow up on incomplete answers or on responses that warrant further attention be the interviewer. Listening to these interviews on tape makes you think the interviewer is merely in a conversation with himself, never hearing the subject.

Over preparation obsession is frequently manifests itself as pre-conception thinking by the interviewer.  A common and easily recognized hallmark of an interviewer bearing pre-conceptions is an overwhelming presence of leading questions and especially the use of short answer questions. If the casual observer where to map the direction of logic of the interviewers discourse he would find that questions are focused toward only one possible conclusion.  Movement of the dialogue to a direction contrary to the pre-conceived charted course is met with resistance and the conversation directed back to the only acceptable conversation thread. This will be obvious despite that fact that often the subject’s responses clearly indicate the dialogue should follow the different track.

Finally, the obsessively over prepared interviewer will frequently find themselves extremely frustrated and impatient with their interview.  He or she will invariably regard their interview subject as belligerent, antagonistic and uncooperative in the face of what the interviewer considers to be overwhelming evidence and logical proof. The frequent result is an interview that degrades into verbal hostilities with marginal or no real productive results.  The interviewer frequently misses opportunities to elicit available information from their subjects due to the interviewer obvious growing frustration.

It is certainly prudent for any investigative interviewer to prepare for all their interviews.  Dispensing with such preparation altogether and forging ahead on a wing and a prayer would be the devil’s folly.  The best advice is to recognize that there is a delicate balance between being prepared and manically trying to prepare for every possible scenario or worse, only one possible scenario.  Preparation is essential but not at the expense of being able to respond to the numerous moments that will arise during the interview that will require you to be flexible to a change in course and react spontaneously to your subject and their behaviors.