Navigating Body Language Signs: Compass or GPS?

by Stan B. Walters
ORCID: 0009-0002-1063-0519
DOI: 10.5281/zenodo.21428927

If you are navigating with a compass and you are off by only one degree, you may not notice the problem at first. Early on, it may look like you are still moving in the right direction. But the farther you travel, the farther off course you become. By the time you realize the mistake, you may be 20 miles from where you thought you were going.

That is the problem with trying to navigate an interview by body language.

Behavioral signs can be noticed, but they are easy to misread and often are. A subject may avoid eye contact, cross their arms, shift in a chair, pause before answering, or show visible signs of stress. Those behaviors may tell the investigator that something changed, but they do not reliably explain why it changed. The behavior may be caused by deception, but it may also be caused by fear, embarrassment, anger, confusion, fatigue, trauma, culture, personality, or the pressure of being interviewed.

The first issue is error. If the investigator starts with the wrong interpretation, every question that follows may begin drifting off course. A nervous person gets treated as deceptive. A quiet person gets treated as resistant. A calm person gets treated as truthful. Like a one-degree navigation error or “course deviation”, the mistake may seem small at first, but it can grow with every follow-up question.

The second issue is the constant need to recalculate. When investigators rely on body language, they have to keep diagnosing every movement, pause, posture shift, facial expression, and change in tone. Is that stress? Is it guilt? Is it fear? Is it confusion? Is it resistance? Is it deception? That creates a heavy cognitive load for the interviewer. While the investigator is busy trying to decode behavior, they may miss the very thing that matters most — the words.

The third issue is return on effort. In our own research, participants who used behavioral cues worked about three times harder, but their accuracy in detecting deception was still barely above chance. That is a poor trade. More effort does not automatically mean better judgment. In fact, the extra effort can become a distraction when the investigator is looking in the wrong place.

The goal of an investigative interview is not simply to “spot deception.” The goal is to obtain reliable information. That requires listening for verbal content: timelines, actions, people, places, sensory details, missing information, contradictions, corrections, complications, and details that can be tested against evidence.

Verbal cues give the investigator a better route. They are easier to identify, easier to explain, easier to document, and easier to test. They also place less cognitive load on the interviewer because the investigator is no longer trying to guess what a movement means. Instead, the investigator is working with what the subject actually said.

That is why body language is more like a compass, while verbal content works more like GPS.

A compass can point in a direction, but it requires constant checking and recalculation. GPS uses multiple points of information and adjusts as the route changes. In the interview room, verbal content gives the investigator those points. It allows the investigator to compare the statement to known facts, identify gaps, test details, and adjust the next question based on information instead of assumption.

Body language can still be noticed. It may alert the investigator that something changed. But it should not be treated as proof, and it should not become the main navigation system for the interview.

If the case matters, the investigator cannot afford to drift miles off course because they trusted the wrong signal.

Body language may point.

Reliable verbal content navigates.

Watch the companion ITIR episode:
For more on why body language works more like a compass while verbal content works more like GPS, watch the related episode of Interview & Interrogation Review here: [https://youtu.be/qHKj_UaadOo]

© 2026 by Stan B Walters All Rights Reserved. Brief excerpts may be quoted with attribution and a link to the original article. Reproduction, redistribution, or use in training materials requires written permission.

About the author:

Stan B. Walters, The Lie Guy®, is an LLRMI instructor with more than 40 years of experience and approximately 50,000 hours of presenting investigative interview and interrogation skills development. Every course he presents is audited against current peer-reviewed scientific research before it is delivered. These skill development presentations can be arranged by your agency thru LLRMI.