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Polygraphs... A Danger to Innocent People?
By Clara A. Thomas Boggs
In January of 1998, the head of the Justice Committee in San Diego asked us to take advantage of a polygraph offered free by a prosecutor who offered to go public and help those who passed it get publicity to help their cases. I put the matter to Robert Rosenthal, an attorney for my daughter. He said "No Way" should we consider this for our daughter, saying that the possibility for false positives is there especially if a test is highly sensitive. He told us that even a breeze coming into the room could trigger something in a person who has spent so much time in prison and who relives the past on a constant basis. He said his experience is that a person who's been in prison as long as my daughter has can take on guilt that doesn't belong to them. Robert also said that the whole point of my daughter's mental makeup is that Strawser manipulated her because she is emotionally vulnerable to manipulation. He said that an accused person goes on being accused in prison and it makes their minds vulnerable.
Robert said he took a polygraph test years ago, and the machine showed he lied when he told the absolute truth. He doesn't trust the polygraph in any way, believing it sets people up, for there is an infinite variety of responses people may have which may be interpreted as guilt but are not guilty. That a person is innocent doesn't mean he or she is emotionally stable enough for a polygraph. Rosenthal said he doesn't want any of his other clients to take such a test.
Interestingly, it was shortly after the time of the Justice Committee's offer that I learned of Brian Pardo's involvement with Darlie Routier's case and of the conclusions he'd drawn from Darin's failure with the polygraph test, and I asked if anyone knew how to get in touch with him so I could send him Rosenthal's information and an editorial in the Miami Herald. No one knew, but as fate would have it, Mr. Pardo has indirectly turned up in my life through the articles Justice: Denied has done about Routier. The offer of a polygraph for my daughter aroused my interest in these tests and I began to collect information since then. I have excerpted bits and pieces for you about polygraphs here, all with proper attribution when available.
Reading a book review of May God Have Mercy: A True Story of Crime And Punishment, about an innocent man who was executed, this line caught my attention:
"Despite a phone call from Mother Teresa, Wilder uses the fact that Coleman fails the lie detector test (a result that surprises no one who knows anything about the polygraph) to deny all appeals for mercy, much less clemency, thereby (at least symbolically) pulling the switch himself."
According to several witnesses of the Darin Routier test, the examiner acted as an accuser, hardly the best environment to test someone who's already in stress. Guilt is a feeling that casts a spell over many people's lives whether it's justified or not. One has only to think about a battered child who believes he is guilty for the abuse he receives to understand this. If the administrator of a test has an agenda, it cannot help but surface and color the interaction between him and the person tested. In the case of Darin Routier, the June 6, 1998, Dallas Morning News reported that Mr. McLemore, Pardo's assistant, said, "The polygraph examiner and Darin were in each other's face. It was a very heated situation."
A "heated situation" is hardly the ideal environment for a test that imposes its own stresses. The burden should be on the tester to be noncommittal and not invested in the outcome.
In November 1997, a Miami Herald editorial, Of lies and justice -- Polygraph Tests, said that a lie detector is only as good as its operator and that some liars can fool machines and operators. It follows that this machine can misinterpret the immense range of human emotion.
"Lie detector" is the common name we use for the polygraph, revealing our naivete more than any truth about it. The polygraph is not infallible, much less an unerring truth machine.
DNA tests are admissible in courts because they are infallible. Polygraph tests have not achieved this success because they are usually unreliable, and are banned as evidence in courts.
The Miami Herald article writer spoke about a former airman who was court-martialed for using drugs, passing bad checks, and going AWOL. He passed a polygraph test in which he denied using illegal drugs and his urine tests were positive for drug use.
Polygraph tests have their uses, but cannot be considered as a way to determine someone's guilt or innocence. If, however, someone claiming innocence passes this test, it warrants looking further into the case for the same reason that we should attend to any claim of innocence. Freddie Pitts and Wilbert Lee used polygraph results to begin a journey that eventually spared their lives and freed them from Florida's Death Row.
Those who distrust polygraph tests have famous company. Sam Reese Sheppard, whose father's murder case inspired the movie The Fugitive, said his father did not take the test because he thought the people conducting the test would be prejudiced against him. The media at the time, however, crucified Dr. Sam for not taking the test. He was eventually vindicated. Dr. Sam Sheppard, now deceased, convicted more than 40 years ago and sentenced to life in prison for the murder of his wife, won a new trial and was acquitted after twelve years of legal battles. His son, Mr. Sheppard, said that after authorities had everyone around his father take a lie-detector test, they said, in effect, "Aha, he did not take a lie detector test, he must be guilty."
Mr. William G. Hagerbaumer, a man who has made it his avocation to study the reasons people are wrongly convicted in child sex abuse cases, wrote, "The basic problem with the idea of using the polygraph to detect deception, is that it does not detect deception. It detects emotional responses in the perso n to whom the polygraph is attached. People may respond emotionally whether or not they are being deceptive. People may fail to respond emotionally whether or not they are being deceptive.
"The studies assume that a polygraph detects deception and then they attempt to measure successful detection of deception, successful detection of non deception, false positives, and false negatives. As there is no direct correlation between emotions generated and deception, there is a wide variation in test results. . . ."
"It is likely that many people will have an emotional response when they attempt to deceive. It is important to realize that there are many other factors that lead to emotional responses. It is also important to realize that not everyone has an emotional response when attempting to deceive."
"Nothing definitive can be said about the results of a polygraph examination. They are used, however, to intimidate people into being more truthful, and can also be used to intimidate people into making false confessions." Another thing to consider is that a sociopath may not believe he did anything wrong and will register as telling the truth when he is lying. Most lawyers can tell us about a client or two who can deceive the machine.
Ian Begg, now a Professor Emeritus at McMaster University in Ontario, Canada, where he was part of the psychology department, wrote to the Witch Hunt Forum: "Polygraphs are recordings of changes in skin conductance/resistance when certain questions are asked, compared to a baseline when other questions are asked. If the change is big enough, the polygrapher might signal the response "deceptive." The basic theory underlying the use of polygraphs is that whenever a person lies, there are physiological changes in the body.Even if the theory is right, in which case the machine could detect intentional lies, honestly mistaken answers are not lies. Even at its best, the machine cannot detect departures from external truths; we need a time machine for that. . . ."
"Polygraphs are not lie detectors, and amytal is not truth serum. These are catchy names, but they imply more than the techniques can deliver. The main use of polygraphs is to bully ignorant people into making confessions. Asking "are you willing to take a lie detector test on your answers" can cause some people to disclose more information, or change their answers. . . ."
"In short, polygraphs are just ‘witness demeanor' dressed up in a white coat. Neither has sufficient demonstrated discriminative validity to detect even intentional lies. And to repeat, no procedure based on present behaviors can determine historical truth. The concern of the current list is most often not with the sincerity of the complainant, but with the reliability of the "memories" as indicants of external reality. Psychologists and polygraphers cannot provide that information. And courts can't either, unless they have corroboration of the factual allegations."
(Since Professor Begg retired in 1998, he has been completing the licensure (articles and bar admissions) for criminal law, working in the real world defending real people charged with crimes.)
Most people don't understand that a polygraph is only a machine that reads physiological responses, such as heart rate, body sweat, and is not a device that miraculously "knows" when someone lies. Poor responses can occur for many reasons. Some people can trick the machine, polygraph results are subject to operator error, and people respond to stress in many different ways. Law officers have been known to trick suspects by using a mimeograph machine that ejects a paper with the report that the suspect is lying. Usually the accused is asked to come down to the local police department and submit to polygraph. The person who is ignorant about polygraphs will often eagerly go to the st ation and let himself be hooked up to the machine believing he'll pass.
Not likely. Police will also often conduct an intimidating interrogation while a polygraph test is in progress, and suspects have reported that officers standing by would pressure them the whole time. Then when the suspect fails the test, the police have their "probable cause."
The number of people who report telling the truth on polygraph tests only to find themselves called liars, plus those who freely admit to having lied and gotten away with it, is troubling, especially since so many people seem to be impressed when told that someone passed or didn't pass the test. There's also the wrinkle that a person will respond truthfully when he or she believes something untrue. If I believe something, it is true for me. So it seems to be with most people. The truth is not established, but my belief is recorded as an honest answer. There is also the fact that people may respond with anger, sorrow and agitation when the subject of the test has to do with a crime. Add to that each person's trigger words, like mother, God, sex, and any number of things, and the unreliability of these tests rises.
People sometimes have emotional responses when they deliberately lie and sometimes do not emotionally respond to telling the truth. A polygraph machine is simply not a lie detector. It will register false positives and false negatives and will vary from one test to the next.
To use polygraphs as lie detectors is to indulge in pseudo science. There is no way to tell if someone is lying or telling the truth if we can't match it against hard evidence and in that case the test is useless because you have the evidence.
The problem with the polygraph's electro-dermal response (EDR) is that there is extreme variance from one person to another on whether or not, and to what extent, mental issues manifest in a body response. We all know people who react in extreme ways to both positive and negative stimulation, while others seemingly have no physical response to the most extreme situations. Highly self-critical people are a case in point. They would tend to have extreme EDR reactions to everything.
Unfortunately, the fact is that we are all impacted when an accusation is made and tend to believe, rather than disbelieve it. We will only make progress when we can assume the stance of a wise parent and work at disco vering the truth.
At the June 1999 American Psychological Society annual conference in Denver, Colorado, several studies presented should make us rethink the way we view lying, and our ability to judge it.
According to the studies, one in 10 people who lie are convinced they're telling the truth, raising fears that some people are immune to lie detector tests and do not show the tell-tale signs of a liar.
Dr. Danielle Polage from the University of Washington did two studies of 140 people, showing that people with a good imagination can convince themselves, after being told to lie, as part of a control group, that they are telling the truth.
The findings of the study show that a majority of people will not be affected by lying about an event, only strengthening their memory of the truth, but a full 10 per cent came to believe that the lied-about event was true and later denied that they'd lied.
The issue of people who make false confessions can be especially pitiful. They may lie when their defenses are worn down or they think they may get less prison time. The irony is that after they live with their lie, they come to believe it.
The congenital liar lays another pitfall for us. Who has not been deceived by a clever liar? They look us in the eye with candor, earnestly, and we believe. People are generally convinced that they can tell when someone's lying. The facts refute their naive belief in their own abilities. Many studies have been done about our infinite ability to be deceived. There is no substitute for investigation and sober thought. Our emotions will mislead us too often to count on them.
There is no magic truth serum. There is no magic machine that can infallibly separate lies and truth. Let us be humble in the face of our own certainty.
Bertrand Russell: "The trouble with the world is that the stupid are cocksure and the intelligent are full of doubts."
"The great masses of the people will more easily fall victims to a big lie than to a small one." -- Adolf Hitler "Mein Kampf"
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