Answer: When their lips are moving.
Have we all heard that joke, or a variation of that joke before? You can replace the word ‘politician’ with ‘lawyer’ and get an equally humorous result. It’s no wonder that the majority of the US congressfolk are, or were once, lawyers.
Both of The Skeptics’ Guide podcasts and The NESS are apolitical entities. That is to say, we never endorse any candidates or political parties, and we try to restrict any political discussions except when politics (or politicians) crosses swords with science or they embrace pseudoscience.
On the other hand, I am a very active observer of the day-to-day happenings in US politics. Politics is as much an interest to me as is skepticism. So when the politicians serve up a pseudoscientific softball, I LOVE the chance to just smash it out of the park.
As this news article reads from October 9th, two challengers for an Indiana congressional seat have agreed to be hooked up to lie detectors during a debate. Indiana’s Ninth District Republican Party Chairman, Larry Shickles, has proposed the idea of the use of “political polygraphs” in an upcoming debate between the three candidates running for that congressional seat.
What really grabbed my attention in this article were the quotes from the Republican and Democrat party chairmen. This one came from Mr. Shickles:
“While this format may be unusual, I feel strongly that voters need to be able to make a clear decision without all the usual spin.”
Mr. Shickles makes this comment as if a polygraph is somehow a safeguard against political spin, when in truth, a polygraph can be used as a tool to enhance or amplify political spin.
Polygraphs are pseudoscientific devices when trying to determining if someone is lying. These tools measure and record several physiological responses such as blood pressure, pulse, respiration and skin conductivity while the subject is asked and answers a series of questions, on the theory that false answers will produce distinctive measurements.
The problem rests in the interpretation of the data. Polygraphers, the people trained to operate the polygraph, interpret the results. Their findings can be influenced by their preconceptions. If they think a person might be guilty before the test, they might be more likely to interpret the results to reflect their belief.
Another problem with polygraph tests are the high number of false negatives – upwards of 12% in some case studies. Couple that with up to a whopping 50% of false positives in studies.
There are many additional factors at work against the reliability of polygraphy. The employ of countermeasures, how drugs affect the subject, the setting under which the test takes place, the psychology of the subject being tested, just to name a few. The basic notion here is that there are no scientific controls at work, and therefore, the polygraph can not be deemed a scientifically reliable lie-detection instrument.
The folks over at www.skeptics.org put it quite succinctly:
“Polygraph testing is a pseudoscience: it is based upon deception – the polygrapher needs to lie and deceive; its effectiveness is based on fear and intimidation; it is biased against the truthful; and it is easily defeated with countermeasures. As such, polygraphy has absolutely no scientific validity.”
Not to be outdone by his Republican equivalent, the Democrat party chairman, Mike Jones, had this to offer:
“Polygraphs have their use in law enforcement, but I don’t see them fitting in a political debate.”
Oh for shame, Mr. Jones. If only you’d come out and blast polygraphs as pseudoscience, your candidate might have gone up several pegs on my political scorecard. Instead, you are helping to continue to spread the myth that polygraphs are useful law enforcement tools.
May I direct your attention to the people over at www.antipolygraph.org. They lay out many examples of people being falsely accused or incarcerated based on the incorrect interpretations of polygraph results.
Polygraphs can be used in courts of law in the United States. The federal and states governments each have their own laws regarding the admission of polygraph results as part of their court cases. In some cases, it is simply left to the discretion of the presiding judge or judges to allow polygraphs to be admitted into the records. According to the folks at How Stuff Works, New Mexico is the only state in the United States that allows for open admissibility of polygraph exam results. Every other state requires some type of stipulation to be met prior to admitting polygraph exams into record. In most cases, both sides of a legal case have to agree prior to the trial that they will allow polygraphs to be admitted.
Like many of the other pseudoscience topics we cover, the polygraph is widely accepted as plausible for no other reason other than our culture has embraced it. Over the decades since the term “lie-detector test” was first introduced, few citizens have taken the time to go and find out if this claim is true. Our cultural laziness has once again gotten the better of us when it comes to the polygraph, just the same as the concepts of flying saucers, bigfoot, and the notion that we only use 10% of our brain.
I believe that the ultimate scientific test of the accuracy of a polygraph would be to hook one up to a politician, stand back and see if the machine bursts into flames in a matter of seconds. Perhaps then I might believe in the machine’s validity.