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{Editor's note: We are pleased to bring you the first of what we hope will be other articles by Mr. Ponticelli, who has impressive credentials in the police and other fields. A bio-sketch may be found at the end of his article.}
The Truth About Polygraph
By Theodore Ponticelli
The accuracy of any polygraph test depends on two factors; the competence and training of the practitioner and the polygraph instrument employed to record physiological changes during the actual detection of deception test.
The polygraph instrument is not a magical device with extrasensory powers. It's simply a device designed to record physiological changes in breathing, blood pressure, pulse rate and galvanic skin change or body resistance and the increase and decrease of adrenaline during the introduction of the test question.
The analog polygraph instrument, when functioning as designed, is 100 percent capable of recording necessary physiological changes in order to make a determination of truth or deception. A faulty instrument will not record reactions that cause a suspect to appear truthful when lying or deceptive reactions when answering questions truthfully. The instrument will produce abnormal patterns that are difficult to evaluate and are therefore, considered inconclusive. The newly marketed computer polygraph is not as reliable as the analog even though test results are analyzed by computerized algorithms to arrive at a conclusion. The polygraph is not a substitute for a thorough investigation. Often an officer assigned to a particular case feels he or she can shortcut procedures by requesting multiple polygraph examinations in the hope of identifying the person that committed the crime. The requesting officer should exhaust all existing investigative leads before requesting a polygraph.
The first problem with the computer polygraph is it is incapable of recording the necessary physiological changes as the analog polygraph instrument. In addition, the computer polygraph is incapable of processing comparative responses and it's known to produce a high degree of false positive test results. A false positive test is when a person tells the truth and the computer polygraph indicates a high degree of deception. An examiner may have a 99 percent lying test result, but 65 percent of those can be false-positive -- innocent, looking guilty. This alone invalidates the computer polygraph although proponents of the computer polygraph attempt to correct the problem by analyzing the test with long hand math and fail to recognize the computer does not record a full complement of physiology as does the analog polygraph. Research at the University of Utah revealed that false-positive test results have a greater risk of error than the false-negative (people who appear to be telling the truth, but are not).
Inadequate training and lack of standards for most polygraph practitioners is the other problem the industry suffers. As a classic example, a police officer who attends a polygraph course for a short 6 or even 10 weeks cannot possibly learn the applied theory of detection of deception and expect to return to their police departments and be competent polygraph examiners. The training should be a graduate degree program with concentrated academics in psychophysiology, human behavior and practical hands-on laboratory research.
The American Polygraph Association (APA) in all appearance should be the watchdog of the industry, but it is no more than a trade association with minimal standards as to what a polygraph school should teach. The APA scratches the surface with school inspections and student review. As a matter of fact, the APA was denied authority by the Department of Education for academically accrediting polygraph schools, therefore, the APA possesses little or no authority to endorse a post-secondary educational institution.
The Federal Government has a polygraph examiner school. They train most federal agents from the FBI, CIA, Secret Service, Drug Enforcement, Defense Intelligence Agency and Military Investigative agencies. During 1970, this author participated in the government's school course that was being systems engineered. Every potential student would receive the same scientifically standard training in order to maintain a high degree of reliability and validity. Since 1995 the school has liberalized its curriculum and does not seem concerned with graduates who return to their agencies and change the procedures without the benefit of scientific research. What was once known as a model school has now sunk to the low depths of academia.
Ironically, those polygraph examiners from federal and municipal law enforcement agencies hide behind their badges and want the public to believe in their accuracies, which isn't the case. The majority of law enforcement polygraph examiners lack intellectual soundness and knowledge of human behavior as related to detecting deception. In addition, most presuppose a person's guilt with lack of probable cause and tangible evidence. As an example, if a woman reported to the police that her estranged husband molested their child, law enforcement has been known to fail to investigate or attempt to prove or disprove the allegation made by the complainant. The estranged husband would then be administered a polygraph test and the results of the test become spurious in many cases. As another example, if a detective informs the polygraph examiner that the suspect is good for the crime, in many cases the polygraph results will be reported as deceptive. Why? Many reasons, although the first is dishonesty or incompetence. The same degree of incompetence in polygraph exists in the private sector and the reason is the same, inferior training and lack of integrity.
In the hands of competent polygraph practitioners the accuracy should be nearly 96 percent with a 4 percent margin of error. However, 4 percent is a large margin when considered inconclusive, this is most always caused by the practitioner and seldom by the person undergoing the polygraph test.
Aggressive interrogation before a polygraph examination is one of several causes of erroneous polygraph test results. Psychological sensitivity, as consistently being accused of a crime one did not commit, can and will produce false positive results.
In the case of John and Patsy Ramsey over the murder of their daughter, Jon-Benet, it is doubtful that the results of their polygraph tests had any degree of accuracy. If anything, the results were inconclusive. Why? Because both Patsy and John were overwhelmingly psychologically sensitized by the news media, therefore both polygraph tests are invalid even if it indicated deception, which this author believes was the case even though Patsy and John were probably innocent. It becomes obvious the polygraph practitioner rendered an opinion based on personal beliefs and not scientific leverage. In the same case, suspects were also subjected to polygraph testing and exculpated. It is this author's concern that the actual murderer of Jon-Benet was set free simply because of incompetence and lack of a scientific approach to criminal investigation.
The polygraph has never been and never should be the panacea of any issue or investigation. However, polygraph better serves the community as an exculpation tool and not only an identification device for extracting confessions. Often a police detective will request that a suspect undergo a polygraph examination and promises if the suspect does well he or she will be released, well knowing the polygraph results will more than likely produce deception. Why is this? Most police polygraph examiners do not want to contradict a fellow detective and integrity is in question or the practitioner is ill trained and doesn't know any better.
No one should have to undergo a polygraph examination if the officer came under political scrutiny. This author participated in legislation to enact a police officer's bill of rights and within spells out that the polygraph will be employed on a voluntary basis. The citizen who is a suspect in a criminal investigation should have the same option.
Reliability of a polygraph technique should not be confused with validity. Reliability is the measurement of the technique, determining continuity and consistency in the use of the polygraph instrument and testing procedures.
Validity of a polygraph technique is determining the accuracy of the entire approach to detecting deception or exculpating a person who is innocent of the crime under investigation. So that abusive use of polygraph is discontinued, the public should be educated and made aware that the polygraph is no more than an investigative aid.
If the admissibility of polygraph evidence is permitted in courts of law the practitioner and polygraph instrument should be the focal point of consideration to the trier of fact.
********************************************** Bio-Sketch of Theodore Ponticelli
Theodore Ponticelli is a former instructor at the US Defense Department of Polygraph School and has been a practicing polygraphist since 1966. During this time, he served in Southeast Asia, where he was involved in war crime investigations. He was also an advisor to countries of the Middle East and Central America. There he advised on methods of determining truth and deception.
During 1988, while assigned to the US Embassy in El Salvador, Mr. Ponticelli participated in a complex US funded, judicial reform program where he addressed issues involving the falsely accused and fabricated evidence. Mr. Ponticelli is a former scientific investigator with the Los Angeles Police Department, and while there, he was involved in internal affairs and organized crime investigations.
He has guest-lectured at Stanford, Pepperdine and Loyola Law Schools in California and is often called upon to advise law enforcement in California, Idaho and Washington and is a contributor to Police Magazine.
Mr. Ponticelli has qualified as an expert witness in Federal District Court in California, New York, New Mexico and Arizona.
©Justice: Denied
