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Challenging The 'Unbeatable' Polygraph
George Maschke writes "Dr. Louis Rovner, a prominent California polygraph operator, has (through PR Newswire) issued a press release titled, 'Polygraph Unbeatable, Says California Psychologist.' All too often, such publicly-made claims by those with vested interests in the perpetuation of polygraphy (a make-believe science that offers make-believe security) go unchallenged. So, I've publicly challenged Dr. Rovner to support his claim and pointed out scientific research that contradicts it, as well as the examples of several notorious spies and a serial killer who have beaten the polygraph. See, A Public Challenge to Dr. Louis I. Rovner."
But while Dr. Rovner asserts that he is "confident that polygraph tests have a 96% accuracy rate when done properly," the scientific community has no such confidence in polygraphy. The National Academy of Sciences recently published a report titled The Polygraph and Lie Detection that concluded that the theoretical basis for polygraphy is quite weak and that that almost a century of research provides little basis for the expectation that the polygraph could have an extremely high rate of accuracy.
George W. Maschke
AntiPolygraph.org
While it is true that you cannot be convicted on the basis of a polygraph, would you want the news that you had failed a polygraph leaked to the press?
Even if you aren't acused of a crime, consider that you can still lose your job because of a failed polygraph.
Polygraphs are bad science; They should not be used as the basis for making decisions.
And the claim that "almost no human being can beat a polygraph test" is flatly contradicted by the research to which I referred in the linked public challenge, wherein some 50% of polygraph subjects were able to fool the lie detector after receiving a maximum of 30 minutes of instruction...
George W. Maschke
AntiPolygraph.org
There was a recent study where a small number of people were able to detect lies with a nearly 100% accuracy. To me, this is far more impressive than a polygraph's results.
What you are referring to is something that is called the "base rate fallacy". This mathematical fallacy occurs when you try to interpret the results of a test without taking into account the frequency of the thing being tested for in the population being sampled.
Taking the claimed 96% accuracy rate as a given, suppose that 1/10K people are terrorists. If I randomly polygraph 10K peple, I'll on average turn up 1 terrorist and 400 false positives. I can only be 1/4 of one percent sure in my result.
On the other hand, suppose I know that 50% of the people working in an office are stealing supplies, but I don't know which. If I test 100 people, I'll get 4 false positives and 48 true positives. I can be 92% positive than any person who failed their polygraph steals office supplies.
The lesson is this: evidence can only be weighed in context. There will probably never be a single test that can determine the truth on its own.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
I've taken one polygraph in my life. I was 19 and full of that sort of moral superiority that comes from the false certainty of youth. I answered all the questions truthfully, especially the one about whether I'd ever smoked pot. I hadn't and thought anyone who did was a loser. In fact, I felt strongly about the subject.
Afterward, the guy puts his arm around me and tells me I passed and that one lie that I told about the pot wouldn't be held against me. He patted me on the back and sent me on my may.
One anomalous response was interpreted as a lie. A faulty technology had convinced a total stranger that I smoked pot when I never had. The report of that session went to my new employer who didn't fire me but did make the report available to another employee who happened to be my sister. To this day, she thinks I've experimented with drugs when I haven't. After all, what's my word balanced against a neat-o cool technology with all those scribbling pens and sensors and stuff, right?
Polygraphs are bunk. People who make their living in that industry are, by my definition, liars and should be shunned.
Yes, I know I'm only one data point. But sometimes it only takes one data point to know when a technology has failed and is not trustworthy in broad application.
One of the spies I pointed out to Dr. Rovner is Ana Belen Montes, who got a job with DIA at a time when she was already a Cuban agent. She passed her polygraph. The one that's supposed to tell whether or not you're a spy...
George W. Maschke
AntiPolygraph.org
I took three polygraphs as part of a process to obtain a security clearance (no, I didn't get it.) I believe the effectiveness of the polygraph has little to do with the 'technology', and a lot to do with the theater surrounding the examination.
From Skepdic:
'It doesn't appease me that many defenders of the polygraph know it is junk science but defend its use because many people confess to crimes during interviews done before or after being given the test. The machine may not be able to detect lies accurately but, as Richard Nixon said, "it scares the hell out of people." The end justifies the means.'
I did not become a vegetarian for my health, I did it for the health of the chickens. --Isaac Bashevis Singer
Falls positives is what I am worried about. People being convicted because they were nervous and upset about being charged with something they didn't do.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
Other agencies that administer lifestlye polygraph examinations, such as the CIA and NSA, do not make their polygraph failure rates public, though I suspect that they are somewhat lower than the FBI's.
In the Department of Defense (which uses a counterintelligence-scope polygraph), virtually everyone passes: the only ones who "fail" seem to be those who make what DoD terms "substantive admissions."
For information on what you might expect during your polygraph examination, and tips on how you might protect yourself against the risk of a false positive outcome, see Chapters 3 & 4 of The Lie Behind the Lie Detector (1 mb PDF).
George W. Maschke
AntiPolygraph.org
Sorry, but I can't allay your fears. I failed the lifestyle polygraph three times. The first time, I was told I was lying when I said I had not committed a serious crime; we're talking rape, murder, extortion, and the like. I assure you, I have not. The first polygrapher also berated me for being vegan.
The second time, I was told that I was telling the truth about not committing a serious crime. Well, I gave exactly the same answer as I had during the first polygraph. Did I uncommitt a serious crime? Did I forget I had committed it since my first polygraph?
It seems, however, according to the polygraph at least, that I was stupid enough to experiment with drugs or to sell drugs sometime between my first and second polygraph. For, during the second polygraph, I was 'lying' when I said I had not.
During the third polygraph, where I was told I am very lucky (for it is apparently very rare for someone to be seen a second time, let alone a third; I assure you it is not rare), I was not lying about not using or selling drugs, but the serious crime problem popped up again.
As an experiment during the third polygraph, I lied when I answered one of the questions about all of the information on my form being correct. I took a trip to Canada (my first time leaving the USA) after my second polygraph, but I never amended my form to include it, because I didn't want to have to go through the hassle. The polygrapher wasn't really interested in my answer to this question, apparently.
It was an interesting experience, and gave me some good anecdotes to share with others, but it didn't help anyone figure out if I was telling the truth or not.
I did not become a vegetarian for my health, I did it for the health of the chickens. --Isaac Bashevis Singer