Darkcobra,

I am afraid your comparison between medicine and polygraphy is more specious than I can bear.  Although the former does contain aspects of art as well as science, it universally recognized as a serious body of knowledge and practice.  This is most certainly not the case for polygraphy.  In fact, surveys have indicated that a majority of the members of what would be the parent science of polygraphy (if polygraphy had any connection to science), psychophysiology, believe (CQT) lie detection to be invalid, easily manipulated, and lacking a theoretical basis for practice. Interestingly enough, both the medical (A.M.A.) and the psychological (A.P.A.) communities that you mention have called for and end to polygraph screening in years past.   I suppose it is best said by Al Zelicoff (M.D.) when he says (quoted on the home page): "If we had medical tests that had the same failure rate as a polygraph, then physicians that use those tests would be convicted of malpractice."

darkcobra2005 wrote on Oct 23^rd, 2005 at 8:39pm:


DarkCobra, 

Eyewitness testimony is only so good anyways and a good defense lawyer stands a chance of nullifying it to a jury. But as we all know the Polygraph test is not admissable in a court of law unless all three parts of the proceeding agree, Judge, prosecutor, and defense. And at best with all three in agreement its a rare occurance. 
And I would never suggest to my client that he ever take a polygraph, unless 1- its with an examiner of my choosing, 2 - in a neutral or positive location to my client.
3 - without any distractions of a law enforcement official being present.  ANd it would only be used if the Outcome is NDI.  Otherwise it won't be used.  And by your own admission the CQT has faults ... unless its 100% accurate its worthless. And I have had this discussion with other lawyers and those of us soon to be. We all believe that the polygraph flaws are actually a help to getting rid of foul device. Keep putting the guilty in jail and be a real interrogator, most really good interrogators I know, from my military experience don't need a polygraph to get the results desired.  Thoughts worth pondering ....   

In my opinion, what renders the polygraph utterly worthless is not that it and its operator fail to detect 100% of the deceptive subjects.  What renders the polygraph worthless is that in addition to failing to detect 100% of the deceptive subjects, it also erroneously “fails” or labels as deceptive a certain percentage of truthful subjects.

If the sole accuracy issue with the polygraph were that it was unable to detect all of the deceptive subjects but it never falsely “failed” any truthful subjects, I doubt I would have a problem with it.

If that were the case there would be some degree of certainty in those tests where deception was detected.  If there were no chance of a false positive then the polygraph would at least be of some use.   

In those cases were deception was indicated there would be certainty that the subject was, in fact, deceptive.  In those cases where no deception was indicated there would still be the uncertainty of whether the subject was being truthful or whether his deception simply went undetected.  Even so, there would be some degree of utility if the polygraph and polygraph examiners were capable of this degree of accuracy.

However, the actual accuracy of the polygraph, which includes an unknown false-positive rate, renders it worthless.   

Given the actual accuracy of the polygraph, a test result indicating deception means that either the subject was deceptive, or that the subject was truthful but is part of the unknown percentage of subjects who register as a false-positive.  A test result indicating no deception means that the subject was truthful, or that the subject was deceptive but successfully employed countermeasures, or that the subject was deceptive but is part of the unknown percentage of subjects whose deception will not be detected.

The percentages of false-positives and the percentages of deceptive subjects who escape detection are hotly debated, but I cannot recall any polygraph supporters who claimed that the correct figure for either percentage is zero.   

That being the case, what more do you know after a polygraph exam than you did prior to it?  If the subject “passed” it means he could have been truthful or he could have been deceptive.  If he “fails” it likewise means he could have been truthful or he could have been deceptive. 

It is not the inability of the polygraph to detect 100% of deceptive subjects that causes the problems.  It is the unknown percentage of false-positives that renders all non-specific issue polygraph test results suspect.

Dear EosJupiter,

My apoligies for the way my last statement was presented.

I am insulted by any agency or polygraph examiner to use such instrument in a "scientific" manner, not by your presentations or opininions (which I was trying to agree with).

That line was presented for the agency advocates of the polygraph prescreening process.

You have been polite and professional with your post. 

Regards.

darkcobra2005 wrote on Oct 24^th, 2005 at 5:37am:


So do you require examinees to sign a waiver of liability before you will agree to polygraph them, as is standard operating procedure amongst polygraphers? Why would you do such a thing if you truly accept responsibility for your actions and their consequences?

It seems to me that the polygraph community has collectively shirked any and all responsibility for its failures and the consequences thereof.

How should polygraphers who falsely accuse the truthful of deception be held accountable?

On the amends side:

DarkCobra,

its not personal, I would never be that unfair .... regards

darkcobra2005 wrote on Oct 24^th, 2005 at 7:58am:


If the form is worthless, then why make examinees sign it? While state laws may require a consent statement be signed before a polygraph examination is administered, they most certaintly don't require polygraphers to demand a waiver of liability from examinees.

Why do most polygraphers demand such waivers of liability? It is clearly not a matter of law. It is a matter of choice. Please don't piss on my leg and tell me it's raining.

Again I ask:

1) Will you go on the record as releasing all examinees you have polygraphed from any liability waivers they may have signed?

2) What do you have to say to your colleagues in the polygraph community who routinely demand that examinees sign such liability waivers?

3) How can such a requirement be ethically justified?

4) Why do your colleagues shirk responsibility for their actions (by demanding such waivers)?

darkcobra2005 wrote on Oct 24^th, 2005 at 8:01am:


While I think any comparison of polygraphy to medicine is entirely inappropriate, I would be skeptical of any doctor who required me to sign a liability waiver before administering a non-invasive, non-experimental diagnostic test. I've never been asked to sign a liability waiver for a urine test. Why should I (or anyone) have to sign one for a polygraph "test?"