When I began teaching others about body language, I would spend at least eight hours of classroom time on different types of gestures found in body language and their possible interpretations. After the instruction, we would watch videos of interviews, interrogations, and people communicating.

The goal was to put to use the information about body language we’d been discussing. The problem we encountered was there was too much information to remember and put into practice so soon after the instruction. Seeing the difficulty the students were having watching the videos while searching through the material to make an interpretation of the kinesics, I needed to come up with something that would help them get organized.

I drew a reference chart on the board to help the students quickly read and identify behavior (a representation of the chart is at the bottom of this article for your use). It worked.

Related articles Consider the 'gentle interrogation' Related feature Interview and interrogation: Breaking the alibi One of the tools we use to help eliminate possible suspects is to ascertain their alibi. True alibis are usually easy to verify with a witness, a video, or other concrete information. The harder alibi to prove or disprove is where the subject was alone or at a function where no one would remember them.

I broke the types of body language into two categories, “Truth and Deception.” Later, I added Positive or Negative Behavior and “Indicator Behavior.”

Indicator Behavior is what we observe to determine which stage a subject is in, so we can respond effectively with the correct “Coordinated Behavior Response (CBR). CBR is not discussed in this article, but it is discussed in great depth and detail in my column about the art of the “Gentle Interrogation.”

Truth/Deception versus Positive/Negative

The two categories of Truth and Deception, when observed, generally indicate the person is being truthful or deceptive. That sounds obvious, but a note here: The deceptive behavior would be responses to questions by the investigator on issues that are sensitive to the subject and generate stress.

If the person doesn’t care, this doesn’t work.

Positive or Negative Behavior indicates whether the subject likes or dislikes the idea being discussed.

For example, imagine that you’re questioning a subject about a theft of money. You ask the person if the missing money could be an accounting error and “will turn up later.”

The person turns into you, opening up, and displays behavior that indicates he likes the idea, that the missing money is due to an accounting error. This behavior is often considered truthful behavior. However, the person is responding to the idea that there was no theft. This is then interpreted as deceptive.

Here, truthful behavior to a negative idea is considered deceptive. It can be kind of hard to get your mind around that, so I just call it positive or negative behavior.

How to Tell a Liar

We came up with five categories of general behavior to look for:

• Behavior: The physical behavior that is observed during responses

• Eye contact: Breaks in eye contact during responses

• Answer: The answer itself

• Timing: The timing of the response

• Voice: The characteristics of the voice: tone, speed, volume, etc.

Now, we divide these behaviors into two groups, “Truthful or Positive” and “Deceptive or Negative.” As you look at the behavior, compare it to the chart. This makes it easier to quickly categorize and interpret the behavior.

Behavior: Evaluate only the behavior that is in response to and resulted from the asking of the question. Do not consider movement that occurs between questions and could be considered movement that is the norm for that person during the questioning.

Eye Contact: Look for breaks in eye contact when the subject is answering the question. A truthful subject will maintain good eye contact. When the deceptive person answers the question, they may break eye contact, however briefly. They may resume eye contact after the question, sometimes as if they are looking to see whether you are accepting the answer.

Answer: Evaluate the actual answer itself. Look for the following characteristics: Does the person use harsh or soft terms? Does the answer spread or focus suspicion? Does the person Include or omit themselves from suspicion? Does the person give you a direct answer or is the answer evasive or non-relevant to the question?

Timing: Check the answer for timing and consistency. Is the answer on time, or are they thinking before answering? The bottom line is to evaluate the timing of the answer with the type of question. As Paul Ekman states, “Is the person thinking when they shouldn’t have to?”

Voice Characteristics: Does the person’s voice tone go up, down or remain in the middle? Is the speech clear or mumbled? Does the voice volume increase in anger when accused or remain neutral?

One word of caution — this model is just a tool to observe and quickly analyze behavior. It is not ironclad, and there is a significant amount of learning required to become proficient at reading and interpreting behavior.