Compiled by Kotie Geldenhuys
A man who was not considered to be a primary suspect in a murder case, sat at one end of the table, carefully crafting his answers to the FBI agent’s questions. Although he had a believable alibi, the agent pressed on with the questions nevertheless. With the suspect’s consent, he was asked a series of questions about the murder weapon:
“If you had committed this crime, would you have used a gun?”
“If you had committed this crime, would you have used a knife?”
“If you had committed this crime, would you have used an ice pick?”
“If you had committed this crime, would you have used a hammer?”
The information of the type of weapon which had actually been used in the commission of the crime, namely an ice pick, had been kept from the public and only the murderer would know about the real murder weapon. As the FBI agent read down the list of weapons, he carefully observed the suspect. When he mentioned the ice pick, the man’s eyelids came down hard and stayed down until the next weapon was named. The agent immediately understood the significance of the eyelid behaviour he had witnessed and from that moment onwards the “minor” suspect became the primary suspect. This man later confessed to the crime (Navarro and Karlins, 2008).
During any typical criminal investigation, the primary focus is normally on suspects’ verbal statements, rather than on how and what story their body is conveying while they are telling the story. Gardner (2018) argues that for all of the words a person says, there are thoughts and feelings which go unsaid. Although these unspoken thoughts and feelings fail to make their way through the vocal tract, there is another type of language which may betray those who want to keep their thoughts and feelings a secret: this non-verbal communication is also referred to as body language. As people are not always aware that they are communicating non-verbally, body language is often more honest than an individual’s verbal pronouncements, which are consciously crafted to accomplish the speaker’s objectives (Navarro and Karlins, 2008). The use of body language interpretation in criminal investigation can provide a useful foundation in determining the direction an investigation will take. A suspect may say all the right things and might not make a single slip of the tongue during an interview, but his/her body language will hint that they are trying to hide something (Gardner, 2018).
When an investigating officer interacts with suspects, both parties continuously give and receive non-verbal signals such as gestures, sitting, posture, eye contact, loud or low tone of voice and distance between individuals. All of these have meanings (Otu, 2015). Segal et al (2013) stress that everything a suspect does, such as the way they listen, react, look and move, might have a meaning to a law enforcement officer. Even if a suspect stops talking, it could still be a meaningful non-verbal communication to an investigating officer.
Forms of non-verbal communication
Navarro and Karlins (2008) inform us that non-verbal communication is a way of transmitting information, similar to the spoken word, except that it is achieved through facial expressions, gestures, touching (or haptics), physical movements (or kinesics), posture, body adornment (such as clothing, jewellery, hairstyle, tattoos) and even the tone, timbre and volume of an individual’s voice (rather than spoken content). Eye contact, space and distance, humour as well as silence can also be added to the list (https://iedunote.com/nonverbal communication).
Otu (2015) divides non-verbal communication into:
- Semiotics which refers to the study of how signs relate to things. When a suspect crosses his/her arms, it may indicate resistance, protection of his/her space or defensiveness. Suspects who feel comfortable, safe and free will always sit in a relaxed, open manner, while suspects who feel hostile, aggressive or nervous will sit in a closed manner, with arms and legs crossed.
- Proxemics which refers to the distance or space between the communicator and the receiver. Papa (2013) writes that if a law enforcement officer moves too close to a suspect, it could be interpreted as an authoritative gesture on the part of the law enforcement officer and if the suspect gets too close to the law enforcement officer, it could be interpreted as insult, intrusion or aggression.
- Kinesics mainly deals with body language, including posture, facial expression, gestures and the way a suspect walks or sits, which can all communicate meaning to a law enforcement officer (Wayne, 2013). Vogler (2013) however stresses that different cultures interpret gestures differently which must be considered when confronting a suspect. Wayne (2013) reminds us that each society develops its own rules for interpreting non-verbal communication while Otu (2006) explains that a double finger “peace sign” in the USA may be interpreted in the UK as an obscene gesture. In a heterogeneous society, it is necessary for law enforcement officers to be familiar with other cultures and how they communicate non-verbally (Bailey, 2013).
Training in the detection of deception
According to Otu (2015), law enforcement officers must be sure that they can communicate non-verbally and decode the non-verbal communication of suspects, regardless of their cultural origin. Since non-verbal communication makes up two thirds of all communication, there is a need for law enforcement officers to have the ability to interpret conscious and unconscious non-verbal communication signs. Non-verbal communication is a powerful tool (Segal, Smith, Boose and Jaffe, 2013). Gardner (2018) adds that like all useful investigation tools non-verbal communication must be studied further as one can only go that far with an untrained eye.
Research into deception, which looks at the facial expressions of people who lie, has found that traces are left on the face after someone has told a lie, but that this only lasts briefly. The research reports: “During and immediately after lying, we found there are definite invisible but significant changes that take place on different parts of the face ... These significant invisible changes last only less than ten to 15 seconds” (Yoshiaki, 2015). It is therefore important that all individuals working in some field within the criminal justice system, be it a police official or a prosecutor, should be trained sufficiently in the detection of deception (Gardner, 2019). Navarro and Karlins (2008) write that facial cues are missed because we have been taught not to stare and/or because we concentrate more on what is being said than on how it is being said.