Polygraph tests as good as tea leaves

I'm going on record right now. I will not submit voluntarily to a polygraph test at any time, for any reason. Even if I'm innocent - especially if I'm innocent.

The use of the lie-detector test has not gone the way of reading bumps on the head and tea leaves as it should have, and people must stand up against it.

Polygraphs are ostensibly used to indicate whether or not a person is lying. However, authorities are always careful to not call it a "lie-detector" because they know it isn't. They say it's a "tool" they use in investigations. Well, it's a tool to find the truth the same as a rubber hose is a tool to get a confession. It's used to intimidate.

The general public believes in this junk science. When a person "refuses to take a polygraph" much of the public assumes guilt. When a defense attorney says "my client will take a lie-detector test" they know potential jurors will think it means something.

It means nothing. In fact, it means less than nothing. The very high degree of false results makes the polygraph "evidence" a red herring. One might as well offer as evidence of guilt that the suspect called heads and the coin came up tails. Even if it was 90 percent accurate (which it isn't), how do we know who is in the 10 percent. Would we accept fingerprints if they were 90 percent accurate?

Study after study after study proves the machine doesn't work. It measures physiological reactions, and can be fooled intentionally or accidentally. Aldrich Ames, the CIA spy, passed his test repeatedly. Thousands of completely innocent job seekers have been denied government jobs because of false readings. The National Academy of Science rejects it, and all courts reject it as phony science.

The dirty little secret behind the "test" is that it depends on trickery, not science. The polygrapher, while admonishing the examinee to answer all questions truthfully, secretly assumes that denials in response to certain questions -- called "control" questions -- will be less than truthful.

One commonly used control question is, "Did you ever lie to get out of trouble?" The polygrapher steers the examinee into a denial by suggesting, for example, that anyone who would do so is the same kind of person who would commit the crime under investigation. But secretly, it is assumed that everyone has lied to get out of trouble.

The polygrapher scores the test by comparing physiological reactions to these probable-lie control questions with reactions to relevant questions such as, "Did you shoot John?" If the former reactions are greater, the examinee passes; if the latter are greater, he fails. This simplistic methodology has no grounding in the scientific method.

Polygraph tests also include irrelevant questions like "Is today Tuesday?" The polygrapher falsely explains to the examinee that such questions provide a "baseline for truth," but in reality, they are not scored at all and merely serve as buffers between sets of relevant and control questions.

Investigators value the polygraph because naive and gullible examinees sometimes make admissions/confessions. But many truthful persons fail the "test." Perversely, the test is biased against the truthful because the more honestly one answers the control questions, and as a consequence feels less stress when answering them, the more likely one is to fail.

Conversely, liars can beat the test by covertly augmenting their physiological reactions to the control questions. This can be done by constricting the anal sphincter muscle, biting the side of the tongue, or merely thinking exciting thoughts. Although polygraphers frequently claim they can detect such countermeasures, no polygrapher has ever demonstrated any ability to do so, and peer-reviewed research indicates that they can't.

To learn how anyone can beat a polygraph test, download AntiPolygraph.org's free e-book, The Lie Behind the Lie Detector (738 kb PDF):

http://antipolygraph.org/lie-behind-the-lie-detector.pdf

Breathalyzers are accurate to a much greater degree than 50% of their reading. I don't remember for sure, but I believe it's closer to +/- 0.001 BAC. They must be calibrated, and require trained techs to operate them. The little hand held solid-state analyzers are much less accurate, are only somewhat accurate for a couple of years, and I some states, are not admissible in court as proof of Blood Alcohol Concentration, but can be used to establish probable cause for an arrest.

Polygraphs have been shown in some studies to be about as accurate as trained criminal investigators in detecting lies. However, this accuracy level is about the same as tossing a coin. (NOTE: being able to detect a lie by comparing it to other sources of information is the only accurate way we have of detecting a lie. Police investigators, analysts, etc. can be better at this than the average Joe, because they are trained and experienced in data analysis.) Polygraph Techs play games to try and convince the subject of the test that they can detect lies. One example is to take a stack of cards. The tech knows what the cards are, but pretends not to. He'll have the subject look a card, one at a time. The tech will attempt to "guess" the card, and the subject will be told to answer "no" to each guess. The Tech will then give a song and dance about how he could tell which of his "guesses" was correct, and how the subject give a particularly strong lie response.

There was a case somewhere, I think down south, a few years ago, where a cop put a colander with wire coming out of it on a suspect’s head and told him that the copy machine was a lie detector. He put a piece of paper in the copier that said, "you're lying", and asked if the suspect was guilty. When the suspect said no, the cop hit the copy button. Confronted with this evidence, the suspect confessed. I believe that's how polygraph tests work too.

http://www.motorists.org/stealthis/breathalyzers.html

Breathalyzers Fail Legitimacy Test

The technological backbone of the nation's anti-drinking and driving crusade is the Breathalyzer test. This is the process where the breath of suspected drunk drivers is tested for the presence of alcohol. The Breath alcohol content is then converted by a standardized formula to determine the Blood alcohol content, which is the actual indicator of impairment. The whole process appears very scientific, very equitable, and very fair. The problem is that the process is not any of these things. It is not scientific nor does it rely on existing and accepted science. It is not equitable in that there is a wide variation in the results from person to person. And, it is not fair given that persons who are not realistically impaired are found "guilty" of drunk driving and persons who may be significantly impaired escape detection as drunk drivers.Blood alcohol content can be accurately measured by a blood test. Blood alcohol content has been generally accepted as an accurate indicator of impairment. Setting aside the accepted fact that alcohol tolerance and effect varies greatly from individual to individual I want to exclude that issue to focus solely on the ability of the breathalyzer to accurately determine Blood alcohol content by measuring Breath alcohol content. Peer reviewed and uncontested studies (LaBianca, Simpson, Thompson et.al.) prove a margin of error of 50 % when comparing breathalyzer estimates of Blood alcohol content to actual Blood alcohol content! That means a breathalyzer reading of .1 % represents a Blood alcohol content level somewhere between .05 % and .15%, hardly a level of precision on which to base an irrefutable presumption of guilt!When confronted with this proven inability of breathalyzers to accurately represent Blood alcohol content some state legislatures, in their wisdom and desire for expedience, have decided to grant Breath alcohol content the same status as Blood alcohol content as irrefutable evidence of intoxication, impairment and drunk driving. This is criminal in its error and implementation. Breath alcohol content is a legitimate measurement of only one thing, the alcohol content of the sample of air it is measuring. It is not an accurate indicator of Blood alcohol content, nor an accurate indicator of alcohol related impairment.Breathalyzer readings should not be considered as per se evidence of Driving While Intoxicated (or impaired) unless the reading is high enough to overcome the inherent 50 % margin of error. That means a Breathalyzer reading must exceed .2 % in a state with a .1 % DWI threshold to be granted per se status (irrefutable presumption of guilt). Breathalyzer readings above .1 % and below .2 % should be accorded prima facie status (rebuttable presumption of guilt). Breathalyzer readings below .1 % should be accorded no credibility beyond providing probable cause for a DWI arrest. In no case should breath alcohol content be considered an accurate measurement of Blood alcohol content or the degree of impairment.The desire to eradicate the deaths, injuries and property damage associated with drunk driving does not excuse the courts or legislatures from their duty to provide just laws that are fairly administered. If standards, limits and quantities are included in these laws they should be relevant to the subject at hand, clearly delineated, and accurately measured. If there is room for substantial error there should be appropriate opportunities for the accused to address those errors in their defense. The "rush" to arrest and punish drunk drivers has badly trampled these principles.

*Use mouthwash and blow sometime!

Never believe an instrument is as accurate as the scale it is reading.

I worked at a refinery that spent half a million on a combustion gas analyzer. The scale read parts per million. The refinery was using hydrogen in the fuel gas because of a surplus of it in their process. This makes the fuel gas much more combustible.

The analyzer alarm and shut down was set at a 1.5% concentration for the new furnace. If I remember correctly the LEL (lower explosive limit) for the gas in use was 2.25% to 2.5%.

When the new furnace was started up they had difficulty with the igniters. The operators blew out the furnace with the forced draft fans until they again had a near zero LEL reading and tried to ignite the furnace. The five million dollar crude oil furnace was turned into confetti! It seems the new gas analyzer had an accuracy of plus or minus 2.5% by volume.

Where a Breathalyzer will print a read-out to three decimal places, IT IS NOT NEARLY THAT ACURATE! You are talking about measuring a blood alcohol level by the rate of evaporation of blood alcohol through the lungs. Lung capacity, breathing rate, a dry or wet mouth, age and smoking are just a few of the variables. A cheaply made analyzer, and that is what ALL breathalyzers are (seen a police department spend half a million or more?) cannot differentiate between grain alcohol and other similar compounds. Some breath mints will set the things off.

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