Tools HR Can Use to Detect Lies During Investigations


HR professionals, probably more often than they would like, find themselves having to determine whether an employee is telling the truth, particularly during an internal investigation where they are being presented with several versions of the same event.

Enter former Justice Department attorney Michael W. Johnson, now with the Clear Law Institute, who from the SHRM Annual Conference “Smart Stage” provided tips and insights to help HR managers assess truth in these difficult scenarios. Johnson related that most of what people think are valid cues for deception (i.e., fidgety, not looking the accuser in the eye, blinking more, etc.) are actually not and instead are more appropriate indicators of stress regardless of whether the person is lying.

In fact, Johnson stressed that a liar is going to make a concerted effort to look you in the eye and not fidget as they don’t want to appear to be nervous. Research has also shown that blink rates go down rather than up when someone is lying. Alternatively, Johnson provided these three tips for uncovering deception during investigations:

(1) Listen, don’t look. Johnson noted that the average person does better at spotting deception where they just hear the person’s version of events (for instance, over the phone) rather than in person as they are less influenced or distracted by that person’s body language.

(2) Require the witness to do most of the talking. If someone is going to lie about misconduct, you want them to lie to you as much as possible and not divulge your suspicions until the very end or, better yet, in a follow up interview after you’ve had a chance to assess the validity of their version upon a review of all the evidence.

(3) Use some or all of the elements of the cognitive interview. The cognitive interview method focuses on the types of questions asked, which are designed to elicit as much detail as possible, making it hard for liars to not contradict themselves. During a cognitive interview, Johnson explained that the interviewer, after establishing a rapport with the witness through casual conversation, asks the witness to “please tell me everything you can and give me as much detail as possible.”

He noted that the best question you have in your arsenal during a cognitive interview is: “Then, what?” When asked to provide this more free narrative, typically a truth teller will be able to provide much more detail given that they actually experienced the event. A liar, on the other hand, will struggle to add in the detail and will provide a very “bare-bones” account.

Another tactic during the cognitive interview is to ask the witness to “draw the event as this will provide a better understanding of what transpired.” Johnson indicated that this exercise will come easier for the truth-teller whereas a liar is more likely to contradict their verbal account when attempting to draw it. Johnson also recommends asking the witness for sensory details (i.e., what they felt, how the lighting was, what they heard), which he says will come easier for the truth teller.

Perhaps the most effective technique, according to Johnson, is the “reverse order” technique where the interviewer asks the witness to “tell them what happened but to start at the end and go to the beginning as this sometimes can help you remember more details.” When required to go backwards, typically the truth-teller will end up adding more detail they had left out, whereas a liar will struggle as presumably they memorized and rehearsed a version in chronological order and find it more challenging to skip around.

While applying these steps does not provide an absolute guarantee on lie detection, by employing some or all of them as well as validating or challenging the account with independent evidence, HR professionals can feel more confident in their ultimate resolution of the matter at hand.

At least until that glorious day comes when a liar’s pants actually do catch fire.