Deception detection: It's all in the attitude
The role of a subject's attitudes in the detection of deception
Certainly the behaviors Mildred observed, such as being late for an appointment, excessive smoking, sitting in a chair far away from the exam room door, awkward attempts at levity, or hyper-awareness of time are not unique to guilt. Nor did Mildred receive any specialized training in detecting deception. Why was she often successful at predicting the outcome of polygraph results?
The subjects all knew what issue would be covered during their polygraph examination
Before coming to our office, each subject agreed to take a polygraph examination that would address a particular issue. Therefore, each subject knew whether or not he or she would be telling the truth or lying during the examination.
Consider the situation where a man matches the general description of a rape suspect and is questioned two blocks from the assault. The investigator never identifies why he wants to talk to the man, but simply asks the man questions about his identity and recent activities. The man may be totally innocent of the rape and yet display “deceptive” attitudes for a variety of reasons (guilt to some unrelated matter, prior bad experience with authority, outstanding traffic warrant, etc.) Behavior symptoms of truth or deception are only valid if the subject knows if he is innocent or guilty of the issue under investigation.
The subjects all had advanced notice of their examination
Field research investigating truthful and deceptive attitudes all involves subjects who have been given substantial notice for their interview or polygraph examination. Common sense would indicate that at least some of the attitudinal characteristics form as soon as a subject is informed of the issue under investigation knowing, at that instant, whether he or she is innocent or guilty of the act. However, attitudes may be somewhat affected by the amount of time that has elapsed between the commission of a crime and an interview.
For example, one of the attitudes commonly observed in innocent suspects is that they attempt to mentally solve the crime prior to the interview. In their mind, they eliminate possible innocent suspects, think about who may be guilty of the crime, and consider how the crime was committed along with possible motives for the crime. Guilty suspects, of course, do not go through this same mental process because they already know who committed the crime, how and why it was committed. It is possible this “crime solving mentality” takes time to develop and may not be apparent in a suspect who is questioned shortly after a crime was committed.
Further empirical support for this premise is offered from investigators who have reported that behaviors displayed by a guilty person questioned shortly after committing a crime (confusion, extreme anxiety, illogical explanations etc.) are not necessarily seen from guilty suspects who have been given notice for an interview and time to prepare responses. Similarly, an innocent subject who is interviewed shortly after being robbed or assaulted exhibits emotions such as fear, dread and anger which are readily apparent as sincere and genuine. However, if the interview is conducted several days after the event, the innocent subject’s emotions are often less intense and more ambiguous.
The observations were made in the same environment
Our lobby offers subjects a fairly limited choice of behaviors. They choose which chair to sit in, how to position themselves in the chair, what to do while in the chair and, if they speak, what to say and how much to talk. Furthermore, the lobby is relatively free from outside auditory or visual distractions. Because of the controlled environment, the subjects sitting within our lobby have very little extraneous stimuli to respond to other than their internal thoughts concerning the upcoming polygraph examination or interview.
Just as an experienced lifeguard can look at 50 swimmers in a pool and quickly discriminate between similar behaviors of frolic and distress, investigators become accustomed to evaluating suspects within a particular environment. A border patrol agent is familiar with how most people behave as they approach the inspection point; a traffic officer knows how the average person responds when pulled over for speeding and polygraph examiners learn to recognize the average person’s anxiety level during an examination.
An innocent or guilty person’s attitudes may manifest themselves differently depending on the environment. For example, a guilty suspect may exhibit quite different attitudes depending on whether the interview was conducted in their home or at a police station. It is important that an investigator interprets a suspect’s behaviors and thoughts as a function of the environment.
The subjects were all operating from a high level of motivation
Subjects who come to our office are facing serious consequences ranging from losing a job and their reputation to going to prison. The innocent subject is highly motivated to make certain our opinion is accurate, i.e., that he did not commit the crime. The guilty subject is equally motivated to convince us that he is innocent. If either suspect fails to accomplish their goal, serious consequences await them.
Consider that an innocent suspect is questioned about stealing a $2000 deposit. The investigator starts the interview in the following manner: “Julie, I certainly don’t believe that you took that deposit but, because of your position, I have to ask you these questions. Did you steal that $2,000 deposit?” Because Julie is not motivated to convince the investigator of her innocence, the attitudes she displays may be quite different from other innocent suspects who are concerned that they may suffer the consequences for stealing the deposit.
Similarly, if Mildred worked in a bank and observed customers waiting in line for an open teller, it is unlikely that she would be very accurate at predicting which customers were going to deposit a check or withdraw money. The customers certainly have different expectations as they wait in line, but no strong drive or incentive to accomplish their goal. Without high levels of motivation drawing inferences from human behavior is an exercise in futility.
The subjects Mildred observed were primarily adults who were not suffering from mental or intellectual deficiencies
Before we schedule a subject for a polygraph examination, we question the client about the subject’s probable suitability for the examination. There are clearly intrinsic factors that can affect a subject’s attitudes such as age, intelligence, psychological and emotional stability. There are also dynamic variables which can cause short-term changes in a person’s attitudes or behavior. Examples of these include drug or alcohol use, fatigue, and emotions.
Given any two random human beings from two random regions of the planet earth, there will be far more similarities than differences. These two random human beings would predictably form the same attitudes based on their knowledge of whether or not they were innocent or guilty of the issue under investigation. The rare exception to this statement is when the person is fundamentally different in some way that affects their thought process or ability to process information.
The “behavior symptoms” investigators rely on to make assessments of a suspect’s credibility are not the direct product of telling the truth or lying. Rather, they are expressions of underlying attitudes the suspect forms as a result of knowing whether he is innocent or guilty of the issue under investigation.
Some events cause very obvious and predictable attitudes, e.g., striking one’s thumb with a hammer. Committing a crime and lying about it, however, does not fall within this category. Not all innocent or guilty suspects respond exactly the same way when questioned about a crime. While they both will form different attitudes, how the attitudes are expressed may be influenced by a number of different factors. Investigators need to be aware of these factors and take them into consideration when evaluating a person’s credibility.
|Back to previous page|