By Dave Thompson, CFI

“Her eyes darted back and forth as if she was thinking of a response…”

“Based on her answers and body language it was apparent that she was lying…”

“He was closed off and withdrawn, it was clear he wasn’t truthful”

“His body language indicated that he was involved”

These are descriptions of:

Victims and suspects after being interviewed by investigators.

Rape victims and homicide suspects.

Innocent victims and innocent suspects.

In the process of an investigation, especially with circumstantial evidence, the truth is not clearly known and investigators often rely on interviews to gain more information.  Throughout these conversations, we observe the people we are talking to and will see multiple changes in behavior, both verbal and non-verbal.  Understanding when somebody may be apprehensive, concerned or anxious is important in any conversation whether it be with a family member, friend, counselor or during an investigative interview.  However, classifying that behavior in absolute terms as truthful or deceptive may lead down a dangerous path.

But, it works!

I’m sure you have had success where you caught your kids lying, maybe a friend or co-worker and it was obvious because of their “tell”.  It’s absolutely possible that you have identified that nose twitch, the lip quiver or the fake cough that seems to correlate with a fib being told by somebody in your life.  However, that interpretation of behavior is built over years of observing and understanding this person’s tendencies and baseline behavior.  Even with all of the experience you have in establishing this norm – there are still times that you have misclassified the “twitch” that you observed.  We’ve all been in that situation where we thought somebody was lying or hiding information, when in fact they were completely truthful but just had something else on their mind.  We have all misclassified behavior by internally defining it as a lie.

What’s the problem?

The obvious issue, and the one that carries some of the heaviest consequences, is in the interview or interrogation.  Even unintentionally, investigators may pursue a suspect in an investigation due to a “gut feeling” based on the behaviors displayed during a conversation.  Yes, I said “unintentionally”.  Investigators often fall victim to confirmation bias which triggers a sequence of events that results in tunnel vision and the dismissal of contradictory information.   An easy example of this is when we look at the clock and see a unique time, such as “3:33”.  That sticks out to us, and if we happen to look at the clock sometime in the following week and it is “3:33” again we start to think that we “always” look at the time when it is 3:33.  We probably have looked at our watches or phones hundreds of times over the week, but we ignore all of the other occurrences and focus on any time that it supports our theory.  This same circumstance can be applied to an investigation.  There may be circumstantial evidence pointing to a specific subject, or the primary suspect has an extensive criminal background.  It’s also possible that a witness has pointed to this suspect as the person responsible.  Now, the investigator may enter that conversation with a bias that this person committed the crime.  Any “nervous” looking behavior only supports that theory and is perceived as guilt or deception.  Whereas, that behavior may be attributed to a variety of reasons – such as the fear that the investigator won’t believe the subjects story.

Outside of the interview room, the misclassification of behavior may also result in consequences as the average juror becomes an “expert” on this topic.  The juror is consistently evaluating the testimony of each witness, the defendant’s posture and the attorney’s presence in the courtroom.  These subtle behaviors may result in the jurors biased opinion and classification as truthful or deceptive regardless of the facts presented.  The same can apply to voters evaluating politicians, hiring managers assessing candidates or first dates evaluating each other.

I’ve got an itch…

We know that people may react differently when lying and that it could come across in a variety of ways both verbally and non-verbally.  Part of this discussion is not to completely avoid the observation of these behaviors but to understand that they may be caused by issues outside of deception.

A victim or complainant discussing with an investigator the traumatic experience of a sexual assault or workplace violence may be a highly emotional or sensitive conversation.  We know that everyone responds to trauma differently, and an investigator should not have any assumption of how a “normal” victim acts. The victim may display behavioral cues that appear deceptive, but it could be a result of anxiety, fear of disbelief or embarrassment.

The context of the situation can also naturally make people uncomfortable.  Think about how your behavior or demeanor may change from talking to a peer to when the boss walks into your office.  How about going out to dinner with life-long friends, versus your in-laws?  Imagine talking to an investigator from the perspective of a subject; even if innocent there is a heightened anxiety, fear of the unknown and discomfort.

Culture, age, mental capacity, drug-use or even the temperature of the interview room can all be contributing variables to the behavior displayed by the subject.  A behavioral reaction due to any of these issues may very well have absolutely nothing to do with deception.   The subject’s eyes darted up to the right – maybe to recall an answer or maybe because they were looking at the clock hanging on the wall.

So, now what?

I’m not suggesting that we ignore physical behavior because we can all learn a lot from observing the people we are talking to.  Public speakers are consistently evaluating the behavior of their audience to determine a level of engagement and interest.  When having a conversation with your boss, a potential client or even a date, it’s helpful to understand your partner’s level of interest, boredom or resistance to different topics.  Behavior is useful, it can be instrumental in exploring areas of concern, but if misclassified it can be equally dangerous.

Being aware of the potential biases that misclassification may fuel and not allowing those emotions to dictate your conclusions is just step one.  Investigators need to be aware that there are many variables that may affect the behavior of their interviewee including culture, gender, education level, and drug-use to name a few.  Utilizing our observation skills to determine areas of concern in which we should explore further would be a more appropriate use of this information.

Our goal in an interview should be to obtain as much information as possible and then be able to corroborate or disprove those details.  Listening for verifiable facts and structuring an interview which elicits that type of information is essential.  The observation of behavioral changes throughout the conversation may give the investigator targets of areas to explore further – but the result should be more information rather than classification.