The act of committing a crime is always associated with an emotional state. Most criminals experience some level of shame, guilt or loss of self-esteem. Others primarily experience a fear of being caught. A very few (the psychopath) will experience excitement and thrill. Because shame, anxiety and fear are all undesirable emotional states, the mind will attempt to reduce these negative feelings by using defense mechanisms. A defense mechanism is a habitually employed adjustive reaction designed to reduce unwanted feelings by distorting or denying the truth.

We all use defense mechanisms to cope with everyday guilt and anxiety. If I am late in writing the monthly Web Tip, and consequently experienced guilt or shame, it would not sooth those feelings by acknowledging that I procrastinated and was poorly organized. To reduce my guilt and shame I may utilize any number of defense mechanisms. I may blame my boss for assigning me too many other tasks which did not leave me enough time to write the Web Tip. I may reduce guilt by contrasting what I did to something much worse, e.g., it was only a couple days late, not a whole month. I may forgive my tardiness by forming a belief that others engage in the same behaviors as I do and, therefore, I am no different than anyone else. There are many other possible defense mechanisms, but these illustrate the concept they all reduce unwanted feelings and are habitually employed. A person does not consciously distort or deny the truth. The mind does it unconsciously.

During an interview, when an investigator questions a guilty suspect about the crime he committed, it can be safely assumed that the suspect has already employed one or more defense mechanisms to help him cope with his crime. The innocent suspect, on the other hand, has no need to reduce guilt or shame associated with the crime under investigation. Therefore, when defense mechanisms are identified during an interview, they should be associated with a guilty suspect. Consider the following examples of responses to interview questions:

Q: Have you ever just thought about forcing a woman to have sex with you?
A: Well, sure. Every guy thinks about that but that doesn't mean I'd follow through with it.

This illustrates the defense mechanism of identification. With identification a subject forms a false belief that others share his attitudes. A suspect guilty of committing a crime would like to believe that he is no different than the majority of the population. The above suspect could be asked, "What percentage of men do you think, at some point in their life, have forced a woman to have sex with them?" A guilty suspect often relates a very high percentage.

Q: Why do you think some people do file a false insurance claim?
A: Maybe to get back at the insurance company for charging such high premiums.

This response suggests the defense mechanism of projection. It can be defined as placing blame away from ourselves and onto someone or something else. The homicide suspect may blame the victim for getting him angry; a burglar may blame an accomplice for talking him into breaking into the home; a robber may blame his addiction to drugs for causing him to have to steal money. Because projection is such a common defense mechanism, the investigator should actively seek information during an interview to help identify who or what the guilty suspect may have blamed for his crime.

Q: What do you think should happen to the person who took this $2000?
A: Well, I definitely think that there should be disciplinary action but I don't think they should go so far as to have the person put in jail unless it was for a very large amount.

When a suspect contrasts his crime to something much worse he is using the defense mechanism of minimization. We all experience some level of relief knowing that something bad could have been much worse. In the guilty suspect's mind, a rape or robbery was not that bad because the victim was not killed. Drug dealers minimize their crime by contrasting the relatively minor drugs they sell to something much harder like heroine. A computer hacker may minimize his crime by contrasting the mere disruption of a commercial web site to breaking into a national security computer and selling information to the highest bidder.

Q: Did you start that fire?
A: No, but I was smoking in the area where the fire started and I have this strange feeling that maybe my cigarette may have accidentally started the fire.

This is a possible example of rationalization wherein a person re-describes the intentions behind his act. Whenever, during an interview, a suspect accepts possible responsibility for the crime in a way that removes criminal intent, rationalization should be suspected. Actual interview examples we have heard from suspects who later confessed include being the person who may have unknowingly thrown away a missing money from an evidence room, a suspect who said he possibly had inadvertent contact with a step-daughter's bare breast when tucking her into bed and a suspect in a hit and run accident who told us he had a vague recollection of maybe hitting something with his car. In each of these cases the guilty suspect reduced considerable guilt associated with his or her crime by accepting possible physical (but not legal) responsibility for it.

Obviously, there are cases in which a suspect may be telling the truth when acknowledging that an act occurred accidentally or inadvertently. A guideline to consider is that the deceptive subject often introduces his responsibility for the crime as a mere possibility. The guilty suspect generally does not come out and say, "It must have been my cigarette that started that fire because it started right where I was smoking and it couldn't have been anything else."

Q: How do you feel about being interviewed concerning this forged check?
A: I feel like I'm being framed for this thing. I don't know why you're talking to me about this. It could have been anybody. Why would I need to forge someone's check when I have my own checking account tell me that?

The defense mechanism involved in this response is displacement. An emotional tirade, especially when it comes out of nowhere and is not accompanied with supporting nonverbal behaviors, is often emanating from a deceptive suspect. A person who feels guilt or loss of esteem because of something he or she did may reduce that feeling by displacing it with anger directed toward the interviewer. Anger is a much easier emotion for the suspect to deal with than guilt because anger is directed away from the suspect toward someone or something else. Guilt or shame, on the other hand, are directed inward and the best way to deal with them is to acknowledge the truth something most suspects do not want to do.

In summary, almost every suspect who has committed a crime will reduce unwanted feelings associated with their crime through the use of defense mechanisms. On the other hand, a suspect innocent of committing a crime has no need to reduce feelings of guilt, anxiety, shame or fear of being caught. Therefore, when a suspect's response to an interview question reveals the use of a defense mechanism, it supports the opinion of deception. As with any behavior symptom, it is important to evaluate the totality of the subject's behaviors throughout the entire interview to look for trends and patterns before a final opinion of truth or deception can be rendered with confidence.