Does the Polygraph / Lie Detector Work ?
How many times when you have revealed at a party or a social function that you are a polygraph / lie detector examiner and the first question raised was, “Do those things really work?” or similar questions. I admit that when asked that question I feel a little annoyed, even mildly defensive at times. After all, when somebody says they there a surgeon, nobody ever asks “Does surgery really work?” Or when somebody says they are a plumber, I never hear anyone ask “Does that really work?” Sometimes those questions to us about polygraph are followed by other remarks such as, “I hear there pretty easy to beat,” or “I hear you just have to put a tack in your shoe, is that, right? How about this one, “They’re not really that good because they are not allowed in court, right?” We in the profession are continually upgrading the use of technology in polygraph equipment and identifying proper techniques. The APA has put together The Meta- Analytic Survey of Criterion Accuracy of Validated Polygraph Techniques based upon published studies.
The APA has developed Model Policies for applications such as Post-Conviction Sex Offender testing plus a number of others, but despite such things, Polygraph’s credibility and reputation continue to be challenged. Personally, I think that much of this thinking comes from entertainment’s illustration of the instrument and the testing protocol. For example, daytime television talk shows frequently portray polygraph tests that deliver “Split Call” decisions, or tests on comical issues far removed from true polygraph practices. I will give you one example: Some years ago our firm was contacted by a well-known Television Show to conduct tests on individuals In their audience. We refused of course, sighting our APA By- Laws but more because of our regard for this portrayal of polygraph testing. We found out later that the issue they wanted tested on that day, and this is no joke, was, “Are your body parts really your own?” I rest my case.
In addition, movies as well as television shows have done so many inaccurate portrayals of polygraph testing over the years that it’s almost impossible to describe the damage it has done to our reputation. At this last year’s conference in Florida, and more as comic relief, one of the vendors had an ongoing video collection of numerous movie and television clips where polygraph had been involved. You look at these and come to the conclusion that it’s no wonder the public has this view of lie detector testing because that was their exposure. I personally can remember a scene from an old television program where the subject had one of the pneumograph tubes wrapped around the man’s forehead.
We also have to blame what was occurring in the polygraph profession prior to passing of the Employee Polygraph Protection Act, before ASTM Standards, and before APA By-Laws were revised. We have all heard stories of individuals obtaining an analog polygraph instrument (or in some cases something that resembled a polygraph instrument) who had never gone to any polygraph school, never had any training whatsoever in polygraph testing, and began conducting what they were calling lie detector tests. Even those who had attended schools were in many cases running highly questionable tests.
Another often heard disparaging comment about polygraph sounds like this, “It’s still not allowed in court because it’s not 100% accurate.” Well, there are two issues here. First, and this often surprises people when I tell them that despite the myths about this, polygraphs are admissible in court when certain guidelines are met, and these guidelines vary from state to state. For example, in my state of Indiana, there is case law that allows polygraph test results in court with no problem in civil cases. Also, regarding sex offenders for example, who are on probation for that offense, polygraph tests results and related testimony are allowed in probation violation issues because probation violations are a civil matter. Also in criminal cases, if both parties agree to the results of the test prior to the conduct of the test, these results can be admitted. This varies in all states so it’s best to do a little research.
Next, about the comment that polygraph testing is not 100% accurate, that’s true, but nothing else in forensic science is 100% accurate either, including DNA testing. As a matter of fact, my former boss, the Prosecuting Attorney used to make hay out of that issue when I would testify. His point was that polygraph studies indicated it to be somewhere between 95 and 98% accurate. But on the other hand, what some might think of as “popular” forensic sciences don’t come close. For example, he would cite: “Ballistics 76% accurate, Handwriting 72% accurate, Fingerprints 59% accurate, Eyewitness Testimony 52% accurate. (per Journal of Forensic Sciences Vol. 23, 1978).
Actually, I think it would be a problem if polygraph were 100% accurate. Imagine the implications this would have in court. Imagine the effect it would have on government and on the public in general. It would undermine even the rights of individuals to be tried by a jury of their peers.
The bottom line as I see it, is we’re always going to be asked “Does the lie detector really work?” What is available to us would be to change our own attitude about such inquiries. Instead of being upset and annoyed, which might be an understandable reaction, it would be better look at it as an opportunity to inform or educate the inquirer. Look at it as a chance to present polygraph today as an accurate forensic science and to enlighten the inquirer on how far polygraph testing has advanced in technology. Use this as perhaps a vehicle to discount the folly proliferated by the media and certain websites that still continue to encourage these inaccuracies. In other words, grab this as a chance to promote polygraph in the positive light that it deserves.