Liar, Liar! Why Aren’t Their Pants on Fire?

interviewing liar

The interviewer, investigating vandalism of the company’s stockroom area, questions the primary suspect asking, “Were you involved in the damaging of company property?” The subject hesitates, averts eye contact, and panic clearly sets in as he hesitantly responds, “Um…no, I wasn’t.”

The interviewer takes note of the gaze aversion, the fidgety hands, and the long pause. With these behavioral cues, the interviewer decides to push a little further in the conversation asking more direct questions of the subject. The subject’s behavior continues to escalate, now shifting his entire posture and crossing his arms. The interviewer has hit a wall of resistance, and the subject refuses to cooperate any further. Both individuals have left the conversation with a negative perception of each other as the subject leaves with frustration that he was not believed, and the interviewer maintains that the subject was lying and dishonest.

This example is common—the classification of subjects as guilty or deceptive based on their physical behavior. However, there is a large problem with this classification as the average interviewer has about a 50 percent chance of being wrong in this identification. In fact, a study performed by Meissner and Kassin (2002) found that investigators who receive training in detecting deception were successful at about a 50 percent chance-level but maintained higher confidence in their (potentially incorrect) identification of truth or lie.

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There are countless variables that cause the unreliability of physical behavior as an indicator of deception. Primarily, we are all different and respond to situations with our unique perspective based on our experience, our culture, and the context of the conversation. Referring to our earlier vandalism case, the employee may have had a negative experience with an investigation in his past causing anxiety and uneasiness in the conversation. Perhaps he was falsely accused before, disbelieved, or just simply mistreated by the interviewer. All these experiences could cause mistrust and nervousness that then translates to the unique behavioral responses.

In this same scenario, there is a chance that the subject of the interview was afraid of whatever threats were made by the actual vandal. If he feels that his safety is in jeopardy and is uncomfortable in his current environment, then it is likely we may observe these same concerning behaviors.

There is also a possibility that the subject of the interview was not involved but knew who was. The behavior was then a result of fear of retaliation or consequence of being acquainted with the actual wrongdoer. Simply put, the subject’s behavioral response could be a direct reflection of his comfort level with the interviewer and the conversation while having nothing to do with his innocence or guilt.

As discussed in prior columns, behavior is an important part of communication but should not be solely used to classify the subject as innocent or guilty. We have all experienced the importance of nonverbal communication over the last year with an abundance of video conference meetings. When taking part in a virtual meeting, we are constantly evaluating the behavior of our peers that are hopefully on “mute.” Observing eye rolls, nodding of the head, note-taking, or any form of acknowledgement is helpful to increase the ability to communicate in a virtual setting. Even the observation of two attendees on a virtual meeting sending text messages to each other while on the call is fairly easy to see (somebody just took that personally). Behavior is important in communication, but there are more accurate and dependable ways to assess a subject’s credibility and truthfulness than a subtle scratching of the nose.

Withholding Evidence

An efficient tool in the detection of a subject’s truthfulness is a comparison of their statements to the available evidence. This tactic must be used in a strategic, structured process, otherwise its value is minimized. If an interviewer asks directly about the existence of evidence, it does not provide as reliable of an indicator of truthfulness. For example, if the suspect in our vandalism case was seen on video in the area of the incident, the interviewer should withhold those details. If questioned directly, “Why do we have video of you in this stock area?”, the subject may respond with a plausible explanation that could be true or false. Instead, the interviewer could withhold the fact that this video evidence exists and ask the subject about his whereabouts at the time of the incident. If the subject vehemently responds that he never was in the area in question, the value of the evidence has increased as it contradicts the subject’s statements.

Detecting Deception vs Obtaining Information

Instead of focusing on a nose twitch or an ill-timed yawn, interviewers should aim to ask structured questions that increase the amount of actionable intelligence obtained. The types of questions asked, their sequencing, and the exploratory nature of the conversation can facilitate increasing the cognitive load of the subject. This concept will not only provide more information for the interviewer but also increase the difficulty for untruthful subjects to facilitate their lie. These open-ended questions, such as “Could you tell me about the events that occurred yesterday?” are strengthened with appropriate active listening and follow-up probing questions.

Interviewers tasked with assessing credibility of a statement must not enter the conversation with a predisposed assumption of the truthfulness of the subject. Instead, they must focus on actively listening to the responses and then adapting their follow-up questions to extract more information. If the subject replies with “Well, I was back in the stock area for a while with a few people, and then I eventually made my way to the sales floor” then the interviewer should be prepared with expansion and echo questions to obtain more details.

Expansion questions, such as “Will you please tell me more about what happened when you were in the stock area?” will increase both the number of details obtained and the difficulty for a liar to streamline their story.

Echo questions will also help clarify by inquiring about the subjective phrases used by the subject, such as “few people?” or “eventually made your way?”.

The goal of the interview should be focused on obtaining as much reliable information or actionable intelligence as possible. Strategies to achieve this goal focus on the structure of the conversation, the execution of appropriate question types, and active listening skills by the interviewer.

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