An earlier web tip discussed the evaluation of inconsistencies within a suspect's statements. Inconsistencies represent factual changes in an account whereas omissions represent expected information not included within a response. It must be realized that both truthful and deceptive subjects will edit (omit) information from an account. Consequently, it is not the presence of an omission that necessarily indicates deception, but rather what was omitted.

To evaluate omissions, an investigator must appreciate that every subject makes conscious or preconscious decisions concerning the "best possible" response to an interview question. If the subject is telling the truth, the best possible response will include accurate information he believes the investigator needs to know to help establish the subject's truthfulness. Consider that a subject innocent of a rape allegation is asked, "What is your understanding for the purpose of the interview with me today?" While there are dozens of possible responses to this question, the following response is typical of an innocent suspect: "A lady is claiming that I raped her in the parking lot outside of Boyd's Tavern last Friday night. I was at Boyd's that night until around 11:00 but I sure didn't rape anybody." This subject omitted a great deal of information from his response such as when he arrived at the tavern, who he was with and how much he had to drink. However, the information he chose to include within his response is his best possible response to the investigator's question to portray innocence.

Consider a deceptive subject's response to this same question: "I guess some lady is saying that I did something to her." This subject very purposefully omitted the nature of the allegation (rape) as well as the alleged location and date of the assault. To include this detailed information would increase the suspect's anxiety which, of course, he does not want to do. In addition, the guilty suspect is often overly cautious not to volunteer information that may not be known about his crime. If the investigator asked a follow-up question such as, "Do you know when or where she is alleging this happened?" and the subject denied knowing that information even though it is documented that he was previously told these details, this strongly supports deception.

Guideline #1: It is suggestive of deception when a suspect omits including important details within a response. A suspect who offers inappropriate claims of ignorance concerning a crime or allegation is often deceptive.

Based upon thousands of interviews, we have found that truthful subjects tend to include certain kinds of information within a response that is often excluded from a deceptive subject's response. One category of this information relates to emotions. If a truthful subject was frightened, upset, angry or frustrated he or she will be open with this information during an interview because emotional states become intermingled with behaviors when recalling a factual occurrence. On the other hand, a deceptive subject's response often focuses entirely on behaviors, e.g., first this happened then that happened and then I did this. To fabricate emotions within the account becomes an unnecessary lie so these are often inappropriately omitted.

Second, a truthful subject will include specific details within their response because they believe the information will be helpful in solving the crime. Deceptive subjects often omit specific information (times, dates, locations, descriptions) because it requires more lies to remember. If this information is elicited during follow-up questions, often deceptive suspects remain vague as to specific details, e.g., "Gosh, I could have arrived home anytime between 5:30 and 7:00 last Friday night"; "I can't remember her ever touching my bare penis but I wouldn't know if she did it while I was asleep."

Finally, when appropriate, truthful subjects may include a spontaneous, unsolicited denial or statement of verification. To the deceptive suspect, unsolicited denials are an unnecessary lie and, consequently, they will omit them from their response. Unsolicited statements such as, "I sure didn't steal any money to cause that shortage", "I never had any sexual contact whatsoever with my niece", or " I never robbed anyone in my life!" are much more likely to be included within a truthful subject's response and omitted from the deceptive subject's response.

During our child abuse seminar, an interview is shown of a high school girl who claims to have been raped in a bathroom at her school. This false allegation, as confirmed through her confession, offers an excellent study in omission. When asked to relate everything that happened on the day of the reported rape she volunteers an emotional state prior to the rape, "I was worried about being late to class because I already had some tardy slips." Yet during her entire account of the rape itself she never once mentions being frightened, embarrassed or experiencing physical pain. She is so vague in the details of the rape that the rapist is not referred to by a specific gender until follow-up questions are asked. Her initial account referred to "someone" entering the stall and, "I was forced up against the back wall" and "I was made to pull down my jeans." The reason the case was referred to our office was that the victim's physical description of the rapist varied greatly over time.

Guideline #2: Truthful subjects include emotions, important details and spontaneous denials within their response. Deceptive subjects may omit this information.

A last consideration in evaluating omissions within a response involves the sequence of information volunteered. When responding to a question it is human nature to place important information before less important information; a subject will prioritize events and occurrences based on emotional impact or novelty. When emotional or novel information is included toward the end of a response, this is suspicious. It strongly supports deception when the emotional or novel event is omitted entirely during an initial response and only surfaces through the asking of follow-up questions.

Assume that during a training seminar in Las Vegas I lost a great deal of money gambling. I need cash to pay for my taxi ride home so I ask my training partner for a loan. Being embarrassed about my gambling losses, I make up a story about having money stolen from my wallet when I left it behind in the hotel room. After arriving home my wife asks me how the course went and I provide details about the audience and location but, of course, omit the fact that I lost money gambling. A couple of days later my wife happens to talk to my training partner who immediately brings up the theft from my wallet. Following that conversation my wife asks me, "Did anything unusual happen during your trip to Las Vegas?" My response is, "Now that you mention it, there was an incident with my wallet where some money was taken but it wasn't that much." Will my wife believe me? Of course not. Being the victim of a theft and having to borrow money to get home would have been the most memorable experience of that trip and, if it really happened, it would have been the first thing I told her about. The fact that I omitted it from my initial description of the trip clearly supports the probability that there was no theft from my wallet.

We hear these kinds of omissions on a regular basis from suspects we interview. A question that often brings out this omission is, "Who did you tell about (issue)?" In one memorable case an alderman, who had recently been indicted by a grand jury for extortion, stated that he had not told his wife about the indictment because he, "did not want to unnecessarily upset her." In another case the suspect claimed that two men robbed him of an $18,000 store deposit yet he never told his best friend about the robbery because, "It was really none of his business." In both cases, the suspects confessed.

Guideline #3: A truthful suspect will include emotional or novel information early during a response. A deceptive suspect may bring up this information at the end of a response or omit it altogether.

In conclusion, often what a subject does not say in response to a question is as important as what he chooses to say -- Omissions represent a conscious decision. Deceptive subjects avoid detailed descriptions of their crime and are reluctant to volunteer information that may not be known by the investigator. The deceptive subject may choose to omit emotional states or a spontaneous denial within his response because they represent unnecessary lies. Finally, the suspect who places emotional or novel information toward the end of his response or omits them altogether has offered a behavior symptom supporting deception. As with all behavioral assessments of a suspect, identifying omissions should be considered collectively with other observations before an opinion of deception can be supported.