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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."
As I read it he isn't claiming the polygraph to be 'unbeatable' and concedes that some people may be able to beat it but most can't and certainly not by reading a book. More importantly, who cares? Last time I checked polygraphs are generally inadmissible by law.
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
Most polygraphs work on the idea of remorseful feelings the subject will have if they report a lie in response to a question. Indeed they are beatable - most murderers and other criminals would not give off remorse when asked questions, thus the machine interprets the response as the "truth". This is the main reason polygraphs cant use these results in court.
Thus, when polygraphs are used, it's important it _not_ be the only tool used. For instance, when the USGov't investigates someone applying for a security clearance, they check everything in addition to using the poly. Credit history, school records, school/military diciplinary records, tax records, medical history, family medical history, they perform various psychological exams, they talk to the guy's friends and co-workers and supervisors, and so on. They ask questions about international travels, friends who are non-US citizens, etc.
This way, when someone "passes" a poly, there's evidence to back that up or refute that result. If the investigate report backs up a positive polygraph result and nothing negative is found (or the negatives are manageable), then the guy can probably be given that clearance. Otherwise - the red denied stamp gets pulled out. Indeed, someone can pass the poly and still be denied the clearance - such as a black eye on the credit report (espionage risk - if the guy falls behind on mortgage payments, he could sell secrets to whomever wants them) or a history of alcoholism (clumsiness with classified material risk - if the guy gets drunk while acting as a courier, he risks losing it).
This is probably why the "serial killer" in the example passed the detector, for example.
You are not alone. This is not normal. None of this is normal.
When advocates of the polygraph make such dubious claims regarding polygraphy as Dr. Rovner did, I think it is important that they not go unchallenged.
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
As part of DSD's 'Welcome Boeing Contractors Day' they were giving out polygraph tests at gunpoint. (Well, not really gun point, but 'you don't take it, you don't come in on Monday morning - idle threat') After being wired, they start out asking really silly questions - What is your name? - Like they don't KNOW already? They chatted with DSB - those positive vetting weenies. They know everything.
I'd just watched a show on Discovery about how to 'defeat' polygraph! Turns out it more or less is beatable with not too much effort - unfortunately, they know when you are doing this, so you end up at a nice big round-table meeting to 'discuss' where and how you figured out how to defeat it.
Unpleasant. Black smear on your record. Suspect. Terrorist. Etc.
Are you listening DSD - I know you read this!
Well, yes and no.
While it's true that the new techniques are better for detecting lies made up on the spot, they still fail against someone who has thought up, "visualized", and/or gone over their story before.
The brain is complicated, but one thing that's becoming clear is that it's not good at differentiating input sources. Without extensive training, it can be unreliable. That's where all the "false memory" stuff comes from and where the pre-visualization "success!" techniques come from. If you visualize something sufficiently, your brain can become convinced it occured. You can even experience this inadvertently: most people have experienced confusion whether events from dreams were real -- this, of course, is the marginal case; sometimes there is certainty, one way or the other, but whether that certainty reflects reality is another issue.
I don't recall the exact study, but there was one of the conformity analyses where a single test individual was in a room of people who were part of the study. Colors were shown, and everyone would say the name of the color. When they showed a green square, everyone said "purple." Some of the time, the tested individual would go along with the group, and say "purple" the next time the green square was shown.
However, a month after the test, a high percentage of the test individuals *remembered* the square as being purple, even the individuals who had said "green." The active part of the brain (according to CAT or PET scans) was memory recall.
I actually may be conflating two studies here, but I think this was the gist. *ding!* No, really. *ding!* crap. Caught again. When I search I find Moscovici which is sort of like the color part of this, and Hoffman, H.G., Granhag, P. A., See, S. T. K., & Loftus, E. F. (2001), Social influences on reality-monitoring decisions. Memory & Cognition, 29, 394-404, which is about external influencing of memory. I'm sure there's more out there...
Evidently, some pathological liars basically tell themselves stories, and happen to believe them at the time of retelling. Their brain activity is indistinguishable from remembering, even though it's fiction, because they have convinced themselves.
Eloi, Eloi, lema sabachtani?
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