Nonverbal Communication Techniques (Body Language)

Analyzing a person's body language is probably the most common technique taught for detecting deception. For most people, knowingly telling a lie creates some degree of stress. This stress will usually surface in the form of a body movement. These nonverbal signals may include the fingers touching the lips, rubbing the back of the neck, fingers running through the hair, crossing the arms and legs and not maintaining eye contact.

Despite its usefulness, there are several reasons why I feel an interviewer should not focus on a person's nonverbal gestures. If your attention is drawn to the interviewee's body movements, then you probably are not listening to everything the person is saying. This is important because people's words will betray them. It may only be one or two words that will let you know this person is being deceptive. If you focus on their hands, feet, and eyes, then you may miss these few words that reveal his true thoughts.

In order to interpret nonverbal signals effectively you first have to establish the normal body movements for the person being interviewed. This is done at the beginning of the interview when you are asking the person questions he should be answering truthfully. Later in the interview when you start asking more sensitive questions you then look for any abnormal movements. A problem arises when you do not have a chance to establish the norms. For example, you may turn on the television and watch a news reporter interview a prominent person. Many times the actual interview will be 20 minutes long. However, for the television broadcast the interview will be edited to 5 minutes. The editors will delete some of the nonessential questions and answers. They will only televise the responses that deal with the issues at hand. As the interviewee displays various nonverbal signals you cannot say his actions indicate he is being deceptive. You do not know what his normal body movements are because you were not able to establish a baseline.

With Statement Analysis, you do not have to establish any norms. Most of the time you can look at one question and one answer and determine if the person is being truthful. You can take one statement and obtain additional information from that statement. This is all possible because people mean exactly what they say.

Another problem with nonverbal techniques is that the information conveyed through nonverbal gestures is not specific. Let's say you do establish the norms for the person you are interviewing. You ask this person if he performed a certain act and he denies doing it. However, while making his denial he displays a nonverbal gesture. Does this mean he is lying? The bottom line is you do not know. The nonverbal signal probably means he was asked a very sensitive question. Despite his nervous actions, he could be answering the question truthfully. Nonverbal cues can tell us if a person is under some stress. However, this stress does not always equate to deception.

Statement Analysis is very specific because people mean exactly what they say. Consider the following question and answer:

Q. "Do you know of anyone who could have done this?"
A. "I can't think of anyone."

This answer may sound good, but the subject has not told us he does not know of anyone who would do this. All he is saying is at this present moment in time he cannot think of anyone. Perhaps with a little prodding he may have a better recollection.

In order to read nonverbal signals, the subject must be present. You have to visually watch him to see what he is telling you through his body movements. With Statement Analysis, the subject does not have to be present. You can use the Statement Analysis techniques when speaking with someone on the telephone. With Statement Analysis, you can take a written statement and determine if the subject is being truthful or deceptive. You cannot use the nonverbal techniques in a telephone conversation or a written statement. With Statement Analysis, you do not have to see the person, hear the person or know anything about the person in order to determine truth or deception.

Micro-Expressions

The latest craze in detecting deception is micro-expressions. These are involuntary facial expressions that are difficult to fake. The problem is, even with training, they are difficult to spot since they occur in 1/15 of a second. This is why the television show "Lie To Me" showed them in slow motion so you could see what they were talking about. Even if you are video taping the interview, it is not practical to watch the tape in slow motion while the interview is in progress. By the time you can review the video tape and see that the subject was being deceptive, he is probably long gone.

With Statement Analysis, the techniques are easy to learn and easy to use. You can get immediate feedback and quickly determine if the person is being deceptive. Whether you are conducting an interview, watching an interview, or just speaking with someone your main focus should be on the person's language. Listen to what people are telling you. Your secondary concern should be the nonverbal gestures and micro-expressions displayed by the interviewee. Body language should be used in conjunction with the Statement Analysis. If a person displays an obvious nonverbal signal, then take note of it. However, if you concentrate on the nonverbal signals you will miss what the person is telling you.

"Research reveals that verbal methods of deception detection are better than
nonverbal methods, despite the common belief that nonverbal methods are more effective."
Association for Psychological Science
Pitfalls and Opportunities in
Nonverbal and Verbal Lie Detection
Published February 11, 2011

Handwriting Analysis

Handwriting is brain writing. While your conscious mind decides what to write your subconscious mind determines how you will write. There are numerous characteristics such as the size of the letters, how much pressure is applied to the paper, the spacing of the words and the slant of the letters that can reveal a person's personality. Not only can handwriting provide insight into a person's character but a person's writing style can also show if he is being deceptive. This is often seen in how the person writes the letter "O." When extra loops or marks appear within the oval this indicates the person may be secretive and possibly lying.

The limitations with handwriting analysis is that it can only be used with a handwritten statement. The techniques cannot be used when analyzing a verbal statement. Likewise, you cannot apply the handwriting techniques to a typed letter, an email or a text message. With so many people communicating electronically, many handwriting experts are beginning to use the Statement Analysis techniques in order to analyze a statement.

Polygraph (Lie Detector Machine)

As I mentioned earlier, when a person knowingly tells a lie it creates some internal stress. This stress may surface in the form of a visible body movement. Subtle changes to the body that cannot be seen with the eye can be detected by a polygraph. This includes an increase in blood pressure, respiration, pulse and skin conductivity. The polygraph examiner will begin by asking the person being tested questions he should be answering truthfully. This helps the examiner to establish a baseline or normal levels. If these levels change when answering questions about a particular issue, this indicates the person may be giving deceptive answers.

The problem with the polygraph is that the results are open to interpretation by the examiner. With Statement Analysis, there is no interpreting. The polygraph can only measure "yes" or "no" responses. The Statement Analysis techniques can be used on short or narrative answers/statements. The polygraph is limited to determining if a person is telling the truth or lying. In addition to determining truth or deception, the Statement Analysis techniques can also reveal additional information within the statement. Lastly, the polygraph cannot be used when interviewing someone on the telephone or when reading a written statement.

Voice Stress Analysis (VSA)

Voice Stress Analysis is based on the theory that stress brought on by lying causes tremors in the vocal cords thus changing the person's voice. VSA uses an instrument that measures micro-muscle tremors which are impossible to hear with the human ear. When the machine detects that a person is no longer speaking within his normal range, it is an indication the person is lying.

Some people say the empirical studies for Voice Stress Analysis have not been very positive. Therefore, promoters rely heavily on personal testimonials as to its validity. Unlike the polygraph, the VSA can measure narrative answers but the analysis is limited to whether the person is being truthful or deceptive. Unlike the Statement Analysis techniques, the VSA is not able to obtain additional information from a statement. The VSA can be used when conversing with someone on the telephone. However, it cannot be used when analyzing a written statement.