Recently, the Washington Supreme Court reversed a rape conviction partially because the trial court admitted an investigator's testimony that the defendant's verbal and nonverbal behavior symptoms were indicative of guilt. While there were other grounds for overturning the lower court's conviction, relevant to this article is the finding that the investigator's testimony constituted a manifest constitutional error that was not harmless. ¹ Even though the police witness did attend a training seminar offered by John E. Reid and Associates, the prosecution did not lay any foundation to establish the scientific validity of behavior symptom analysis nor was there a judicial ruling that the investigator should be considered an expert witness in the detection of deception.

Before a witness can offer opinion testimony based on scientific evidence, the court must first acknowledge that the proffered evidence is generally accepted by the scientific community. Second, the witness must demonstrate, through education, published research or experience, that he or she is an expert in the particular field.

The staff interviewers who work for John E. Reid and Associates have completed 882 hours of post-graduate classroom and internship instruction in the detection of deception. They are licensed detection of deception examiners and most have published and participated in scientific studies relating to the detection of deception. Many of the staff hold a Masters of Science degree in the detection of deception. Even with this background, only on rare occasions has a court permitted our staff to offer opinion testimony based on behavior symptom analysis. While there is no question that our seminars greatly improve an investigator's ability to detect deception, the training received during the seminar is insufficient, by itself, to establish an investigator as an expert witness in the detection of deception.

Without expert witness status, the testimony of an investigator is generally restricted to reporting factual occurrences, e.g., what was seen, heard, smelled or felt. With respect to a suspect's behavior during an interview, the investigator should always testify about lies the defendant told during the course of the investigation. Consider that a defendant in a homicide case initially told the police that he did not see the victim on the day of her death but later, when presented with contradictory eye-witness evidence, admitted visiting the victim the day that she was killed. In this case a jury may give marginal weight to the fact that the defendant saw the victim on the day of her death. However, the fact that the defendant initially lied about being with the victim takes on huge significance.

Similarly, because behavior symptoms represent objective observations, an investigator may be able to offer this testimony during direct examination. However, it is important that the witness restrict his or her testimony to observations, and not draw an opinion or conclusion as to the defendant's guilt or innocence. As an example, the prosecutor could initially ask the witness to describe the defendant's demeanor or behavior during questioning. Depending on the actual behavior observed, the investigator's testimony could be as follows:

"The defendant evaded answers to specifically worded questions."

"The defendant appeared unconcerned during the interview and laughed about the allegations."

"The defendant exhibited little eye contact when questioned about (issue), yet displayed normal eye contact when answering background questions."

"The defendant was very guarded and volunteered little information."

"The defendant turned the lower part of his body away from me and crossed his arms and legs when we discussed (issue)."

Once the defendant's behavior symptoms have been entered into the court record, the prosecutor could rely on the jury's common sense to interpret the meaning of those behavior symptoms. On the other hand, the prosecutor may consider further developing the behavior symptom testimony. In doing so, the prosecutor and investigator must walk a fine line between the witness offering an opinion of the defendant's guilt or innocence (which is generally impermissible) and the witness relating prior experiences, which are generally admissible. A theoretical dialogue could be as follows:

Attorney: "Mr. Jayne, as an investigator have you encountered other subjects who displayed similar behavior to the defendant's when you questioned them about a crime?"

Witness: "Yes I have."

Attorney: "In those situations, after evaluating all of the evidence and the final court decision, has the person who displayed those behaviors turned out to be more likely telling the truth or lying?"

Witness: "More likely lying."

By approaching the interpretation of the defendant's behavior symptoms from a perspective of the investigator's past experiences, the jury is able to place their own weight on the defendant's behavior or demeanor during questioning.

The previously mentioned court ruling, in no way, alters our recommendation that an investigator should actively document, in writing, important behavior symptoms exhibited by a suspect during a formal interview. If the defense attorney chooses to "open the door" during cross examination by asking questions about the documented behavior symptoms, the witness can explain to the court that making behavioral observations is considered a standard and acceptable interviewing practice and that the information is beneficial in assessing a person's credibility. However, the investigator's field notes should not reflect a specific opinion relating to the suspect's guilt or innocence based on behavior symptoms. Similarly, a written report should not offer a conclusion that the investigator formed an opinion of the subject's guilt based on behavior symptom analysis. It is often preferable to indicate that based on all available evidence, a particular individual could not be eliminated as a suspect.

Courts require that scientific evidence must reach a standard of general acceptance before it is admitted in a criminal trial. Detecting deception through behavior symptom analysis has not achieved that level of general acceptance. However, an investigator can testify as to factual observations that occurred during an interview. This would not only include the defendant's admissions to such things as having opportunity or motive to commit the crime, but also the fact that the defendant initially made false statements to the police. Furthermore, investigators may be able to testify with respect to a defendant's behavior symptoms during questioning if the testimony is limited to factual observations. It is important that testimony regarding a defendant's behavior be presented in such a way so as not to unduly influence a jury's ability to make their own determination of the defendant's guilt or innocence.