Criminal Polygraph Testing


HandcuffsCriminal Polygraph Testing Rates

Our Criminal Polygraph Examinations start at $250 with testing periods running anywhere from 1.5 to 3.5 hours. Please contact us to discuss your specific case and/or schedule an exam.

More About Criminal Polygraph Testing

Criminal polygraph testing is a specialized field. The most experienced polygraphers usually are the ones assigned to these cases. These polygraph examiners should be nationally certified, which indicates that the examiner has gone through a significant amount of training over the past years, has graduated from an accredited polygraph school, and has continued to advance himself within the profession through ongoing schooling. His instrumentation, scoring, and interviewing techniques should be kept up to or surpass that of the profession.

Criminal polygraph testing is usually one in which the subject is either accused of a crime or has already been convicted of a crime. There are prosecutorial polygraph examinations in which there is a strong effort to ascertain a confession if indeed the subject fails the polygraph examination. There is the defense polygraph examination, where obviously if the subject shows deceptive criteria on the polygraph examination, there is not usually a strong effort to elicit a confession. Both the defense and prosecutorial polygraph testing pretest interviews and tests themselves are very much the same.

There are basically two primary techniques used to conduct a polygraph examination of this magnitude. The Reid mixed general question technique usually has four relevant questions with control questions for comparison. The zone of comparison technique usually has three relevant questions. This technique also uses the control question technique for comparison.

For example, a control question is a known lie or a probable lie that should stimulate reaction on the polygraph examination that should be at approximately the same level as the relevant questions. Obviously the accused crime is going to evoke a reaction on an innocent subject. That is why when the examiner scores a polygraph examination he will often not give any negative score unless the reaction to the relevant question is twice the amount of the reaction than to the control question.

In a criminal polygraph examination, the subject’s information has already been relayed to the polygraph examiner even before the subject appears at the polygrapher’s office. The polygrapher has already read the police report and/or a report to the examiner by the subject’s attorney. A prospective list of questions has already been prepared by the polygraph examiner for the pretest interview.

When the subject arrives, they will always sign a consent form to the polygraph, which is mandated by the polygraph profession. The polygraph room will be rather isolated, quiet, and neutral. The polygraph examiner will elicit background information regarding the allegation and the subject’s history with similar situations in the past. The subject’s health history, criminal history, and background will be discussed, then prospective relevant questions and control questions will be developed.

After the subject and the polygraph examiner agree to relevant, control, irrelevant, and sacrifice relevant questions, the polygraph examiner will explain how the polygraph works and then attach components, conduct two, three, or more charts, as well as the control test. At that point if the subject cares to he or she can leave. Usually the subject will stay in the polygraph room while the examiner scores the charts. The polygraph computer will also score the charts if a polygraph computer is used.

The old standard analog ink pen polygraph that the public has come to know is becoming somewhat outdated and does not afford a computer scoring. It is solely dependent on the examiner scoring, which has been considered by many to be the most subjective form of polygraph available today. The old analog has been an extremely effective and reliable form that has worked very well in the past.

Once the polygraph examination is scored and graded, if the subject passes the polygraph examination obviously the post test interview is relatively short. If the subject has failed the polygraph examination, usually there is a more complete post test interview that takes place to either ascertain a confession or ascertain why deceptive criteria was noted on the polygraph examination. Statements are usually made and provided to police agencies. In the case of a defense polygraph examination, a statement will usually not be required and the examination is thus terminated.

Defense agencies using criminal polygraph testing will often seek a report if indeed a subject passes a polygraph examination and has good supporting documentation and video taping to provide to the prosecutorial agencies in these cases. The reason for this is to let their experts review the polygraph examination to make certain it is acceptable to their high standards.