187Dick wrote on Apr 1^st, 2006 at 11:10pm:

Rather than changing the subject and getting into the criminal justice system and the medical profession, let’s try to stay on the topic of the polygraph.   

I applaud your suggestion to use a common sense approach in the debate on the validity of the polygraph.  Let us endeavor to do so.  My suggestion was not to scrap the polygraph because it has not achieved deception-detection perfection; it was to scrap the polygraph because it does not work at all.

Looking at it from a common sense perspective I don’t see how you can argue in favor of using a deception detection system that does not, in fact, detect deception.   

As an intimidator used to scare people into making a confession, the polygraph performs admirably if the person being interrogated believes it is capable of detecting lies.  If they do not believe that then the polygraph is worthless in that regard.

When used as a device used to measure a subject’s heart rate, respiration rate, and galvanic skin responses, the polygraph functions admirably in that regard as well.  Does that correspond with an ability to detect deception?  Not according to me, not according to many others on this site, and not according to the Office of Technology Assessment or the National Academy of Sciences.

Falling back on the argument of, “It may not be perfect, but nothing else comes close” is what is truly flawed.  When assessing the validity of any system or tool the only common-sense way of doing so is to determine if and how well the system or tool performs its assigned function.  If it does not do so (like the polygraph and its inability to detect deception) then it is wholly irrelevant how much better or worse it is than other systems or tools that likewise fail to perform the same function.

nonombre wrote on Mar 25^th, 2006 at 6:57am:

Electronic devices these days have to meet FCC Class A(commercial) emission standards, a byproduct of which is that they tend to pick up less external interference. However, butt sensors are strain gauges and could be exposed in such a way as to meet FCC regs but still pick up EMF. Things that rub can produce astonishingly high voltages producing ESD (electro-static discharge). These would have a different spectral characteristic than strain changes due to motion and could well benefit from "filters" - if it's a problem. If this problem is suspected, the polygrapher could mitigate it by spraying the seat with one of 3M's anti-stat sprays. This lays down a thin, surfactant film that prevents and drains off static.

Marty

Mr. Mystery,
     I agree with you that the polygraph does not detect deception, and that is not what is designed to do.  But the system, which is a polygraph being used by a trained examiner, using a very reliable method of question formulation to stimulate responses to specific questions is a very good method of detecting deception. 
     Interestingly enough, I have seen plenty of people take the test who stated they did not believe it worked, and later admitted to deception when confronted by the results of the instrument.  If the system did not work, how would you explain those results?  That it was just mere chance that the instrument detected very slight physiological changes at the point specific questions were asked?
     I think most of the people on the anti-polygraph side of the arguement even have to admit that there is sufficient evidence to support the claim that the system works.  The most common argument I encounter is over the rate of reliability and specifically, on the issue of false positive responses.  Is there a danger that an innocent person will fail the polygraph exam due to a false positive response?  The answer is yes, that is one of the dangers of using the polygraph.
     That's where we get into the argument over what is fair as far as how the system is used and if there really is a need for polygraph examinations.  My belief is that the polygraph system is very good at detecting deception, which makes it extremely valuable to many different entities.  I also believe that over reliance on the use of polygraph is a danger that needs to be adequately monitored to protect innocent people from false positive results on the test.

Eos,
    I'm surprised that you feel those two statements would disqualify me as an expert.  The first statement, that the polygraph does not detect deception, is a simple fact.  The polygraph only detects and records physiological changes in the body.  Anyone who claims anything other than that is definitely not an expert on the use of the polygraph.
    The second statement is in regards to quality control efforts on the use of the polygraph.  From my standpoint, poorly trained or unethical examiners present the biggest threat to the polygraph community because they bring down the reliability rates of the rest of the profession.  They claim to be experts in the field of forensic psychophysiology and yet know very little about why polygraphs work.  They don't know how to set up and run a proper polygraph exams, and yet their results are factored into the validity and reliabilty studies.  I would think that whether you support or oppose the use of the polygraph, you would not want those people administering polygraph exams.
    I agree that the APA does not have sufficient control over the polygraph community enough to effectively eliminate bad examiners.  I am in strong support of state regulations implimented to quality control the profession.  (I don't support federal control because it would then be controlled by DoDPI).  
    

I'm sure we will talk again,
Take care.

EosJupiter,

You write:
Quote:


I don't believe so...  What goes on with regard to diagnostics by and large is not about good and bad (although there may well be good and bad individuals in practice) polygraphers, ethical and unethical ones, trained and untrained ones, qualified and unqualified ones or federal vs state and local examiners.  This about practicing polygraphers and those who are retired.  Those who are practicing (lie detection) are involved in quackery and those who are retired used to be involved in quackery.  The exception to this simple algorithm would the small (overall) minority of polygraphers in Japan (and elsewhere?) who are involved in the full-time utilization of concealed information testing for diagnostic purposes.  All of the rest of the nonsense should be stopped.

Drew,
    The use of the polygraph in lie detection efforts has been proven successful in hundreds of studies by both the propolygraph community and the antipolygraph community.  Once you admit that there is a higher than average, verifiable accuracy pattern of detecting deception by experienced examiners using polygraph instruments, then you have to admit that there is a level of effectiveness in the use of them.  I have reviewed hundreds of reliability and validity studies, and all of them show a level of accuracy in the ability of examiners to detect deception of subjects being tested with the use of the polygraph.  
    I have not seen a single study that showed the level of effectiveness of single issue polygraph exams to be at or below where the average (50% on yes/no responses) would be.      
    The argument is simple, does attempted deception trigger responses in a subject's body from the sympathetic nervous system, and if so, can those responses be detected by instrumentation?  
    I believe research has proven that statement to be true in most cases.  My concern is the level of accuracy of the system.  (Which I measure in false positive responses).  Because my first hand experience involving the administration of polygraph exams has proven extremely reliable, I am of course in favor of the use of the polygraph to dectect the fear of deception.
    Now you seem to dispute any accuracy of the polygraph testing process.  While I certainly believe you are entitled to your opinion, I would like to know what you base it on.  
    I will look forward to hearing from you.


I'm sure we will talk again,
Take care.

Poly,
    I support the use of the polygraph for pre-employment screening.  I'll admit that multi-issue tests are less reliable than single issue tests; however, I still believe it's a valuable tool (when used with a very thorough background investigation) to evaluate potential employees.  While I know the system is not perfect, I know of numerous law enforcement applicants (including lateral candidates from outside agencies), who have admitted to some very serious felonies after failing the polygraph.  Interestingly, almost all of them were due to failing specific issue tests after showing deception on multi-issue tests.
    I also know the stress of taking a polygraph exam can make the experience rather traumatic, even for the innocent person; however, hundreds of thousands of people have passed the polygraph exam by doing one simple thing, telling the truth.  The main reason I come to this site is to hopefully infulence innocent people who have to take a polygraph exam to not get caught up believing they have to try some sort of countermeasures to pass.  I have seen far too many people fail the polygraph because they tried to conceal something that would not have even disqualified them from the position, than have failed  because their previous actions did disqualify them.
    Because I have fisthand experience with the polygraph, I don't doubt it's effectiveness when properly used.  

I hope I answered your quesiton,
Take care.

187Dick,

One thing I have noticed is that a lot of Polygraphers admit there are problems with pre-screening polygraphs however they all take the "you have to break some eggs to make an omlet" stance.

Depending on what side of the table your sitting on I can see how you can feel comfortable maintaning that opinion.  My side of the table is full of hopes, dreams, motivation, aspirations, skills and ability.  Yours has the "box" and the ability to trash everything on my side.

I for one don't understand how any applicant worth their salt wouldn't look at the drug requirements on the agencies website before applying.  I believe the vast majority do and those that don't fall in the guidlines don't apply.  Of course I have no proof of this, it is only my opinion.

This creates an applicant pool where in my opinion the vast majority meet the drug guidlines.  But somehow agencies like the FBI find a 50+% failure rate acceptable.  Frankly I think the questions regarding national security are a formality.  I would love to see the % + or - difference between how many applicants are rejected for national security vs. drug questions.    Maybe that's not a fair question because naturally we are not a country full of spies....but wouldn't that bias make it so, so difficult to find a spy.

Sorry for all the random observations....

-polywantahcracker