Gentlemen:

I do applaud the taping of the Westerfield polygraph by the SDPD.  This is behavior that I would prefer to see with ALL polygraph exams across the board - criminal investigative as well as pre-employment screeening.  This is absolutely the best insurance for not only the examiners, but the examinees.  

As for the Westerfield case polygraph, I still cannot make the stretch that because he failed the polygraph exam and was convicted of the crime, then the polygraph is a conclusive and valid measure of deception. There continues to be a huge diferential between polygraph results and either charges or convictions.

Case in point:  Brian Kelly, of the CIA passed the polygraph, yet the investigation went ahead full force.
*see thread on this site*
Case in point:  Former mayor is charged with three counts of murder after passing two polygraph examinations.  This case can be read at http://www.roanoke.com/roatimes/news/story144110.html

If every time someone failed a polygraph the end result was a conviction in a court (in criminal matters, obviously), then the pro-polygraph community could wave their statistics and gain more support for their belief in the practice.  However, this is NOT the case.  In the real world, the polygraph has shown to be the thing that is paraded in front of the media when it is consistent with the findings of a court, and shamefully hidden when they do not.

Also, the Westerfield case addresses the utility of the polygraph - the miniscule debate left remaining after the validity of the polygraph was shown to be a total flop by the NAS report.  As for utility, it does in fact have some scintilla amount for which the polygraph community can claim ground.  I have no issue with the use of any prop to wade through criminal investigations, but I do have issue if the results of an exam are the basis of an investigation or any other life changing event - as is often the case with prescreening issues.  

Best,
Seeker

It is highly likley Westerfield did in fact fail the poly since, unlike in screening cases, the police had known about past violent events about that Westerfield would and did lie about. That makes for a much better CQT as the control questions are the CQT's Achilles' heel. Extrapolating this to be a validation of screening poly's with assumed PLT based CQT's is more than a stretch.

-Marty

Ray,

You make reference to the Westerfield exam and the examination of (I believe) six others.  The one link I see to tapes begins with the poly question review with Westerfield (does not contain the other prior portions of the pre-test interview) and continues throughout his in-test phase and interrogation.  This (although better than many polygraphers do) is not a complete recording of all that took place with Westerfield and contains no information from the other six you claim to know something about.  If you can provide complete information, I will take the time to review the material.  Until then, my assessment remains as previously stated...

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anonymous,

Did you listen to the tapes?  Tell me where on those tapes the examiner shows any bias.  If there was any bias, the tapes would reveal it.  That's a typical response from your side of the house,  "The examiner manipulated the test."  That would be easy to prove in this case....so prove it.  

Ray wrote on Feb 8^th, 2003 at 1:30am:


You are assuming facts not in evidence. There is no proof that the others who were polygraphed passed or failed their respective polys. In all likelihood the interrogator was simply lying to Westerfield in an attempt to extract a confession.

Ray,

I would suspect (assuming the facts have you have presented are correct) that the odds on most probable explanation is that the investigating officer(s) had correctly identified (had strong suspicions relative to other suspects) Westerfield as the guilty subject before the administration of the various exams.  The influence of investigative bias is very strong and can lead to either a large number of correct results or a large number of wrong results depending on the nature of that bias.  It is for this reason and coupled with the fact that case investigators are generally pretty skilled at identifying guilty parties (leading to a higher percentage of guilty subject polygraph exams than chance would predict) that you and other polygraphers are largely blind to your actual/unassisted error rates in real field cases.  You should thank investigators every time you get a yearly job performance rating...

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George or any anti-polygraph individual,

I'm still waiting on your response to the above quote.  The polygraph goes seven for seven in a child murder case.  Maybe the polygraph has some validity.  This is a real world example of the polygraph at work.  How do you dispute this?

Ray wrote on Jan 16^th, 2003 at 3:52am:


Since you, George, and I all believe that taping is a valuable thing why do you suppose there is such resistance in the polygraph community to taping? What would you do if you were examining someone who insisted on taping, perhaps even bringing their own recording device and offering to leave you a copy?

I think taping is sometimes resisted by both some examiners and some examinees. People fear being second guessed. It's natural but I think it is far better to have a tape than a she said - he said bitching contest.

Give people credit. I applaud the SDPD's taping.

-Marty

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You scream that all polygraphs should be taped because examiners are often times "cruel" to examinees.  Then, when an exam is taped and the examiner is found to have acted in a professional manner you attribute his or her behavior to the presence of a recording device in the room.  Are you basing your opinion that most examiners act unprofessionally when conducting an exam on statements provided by individuals who have FAILED a polygraph?  What evidence of examiner misconduct do you have other than what bitter examinees have told you?  I think the polygraph community has offered proof in the form of these tapes that even when faced with a child murderer, professional conduct is the norm.    

Quote:

Actually, the SDPD administered a total of seven polygraphs in the course of this investigation.  Both parents and four family friends passed exams.  Only Westerfield failed.  I think that gives it a bit more "statistical meaning."

Ray wrote on Jan 15^th, 2003 at 5:00am:


Ray,

I think that the Westerfield tapes provide a very helpful example of a polygraph examination, and are largely confirmatory of that which is contained in Chapter 3 of The Lie Behind the Lie Detector. The two tapes of special interest with regard to polygraphy are these:

"Pre-test" Phase

"In-test" and "Post-test" Phases

That Westerfield failed the "test" is not indicative of any validity for polygraphy -- a sample size of one is statistically meaningless. In addition, while polygrapher Paul Redden told Westerfield that all others polygraphed about the disappearance of Danielle Van Dam "passed," it is not clear that such is actually the case.

It is apparent that Westerfield had not researched polygraphy prior to his "test." Had he done so, he no doubt could have easily picked out the probable-lie "control" questions and might well have beaten the "test" by augmenting his reactions to them, and perhaps deflecting suspicion away from himself.

I don't know if "professional" is the right word to describe Paul Redden's administration of the polygraph interrogation of David Westerfield, but I would agree that his conduct was civil throughout. I think that SDPD's commendable practice of recording polygraph (and other) interrogations helps to assure such conduct.

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It is generally agreed that the polygraph's greatest reliability is in specific incident testing with a naive suspect. We have that in spades here. Even more to the point, we have a control question from interviewing others that is very specific to Westerfield. That reduces the false positive likelihood from exceptionally honest individuals. Still, it's too bad that CQT testing is so ingrained that SDPD missed a great opportunity to do a GKT on Westerfield. (specifics of the home interior, girl's bedroom, etc).  Perhaps he would have totally caved and spared the county a ton of money.

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This is true but give SDPD credit for taping the thing. We would all be better off in all departments taped.

-Marty

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Even a broken clock is right twice each day. A single anecdote provides hardly a large enough sample size to declare polygraphy reliable.

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Audiotape has a funny way of making a professional out of anyone (obviously excluding applicant situations where the examiner knows that there will be no chance of the tape ever getting into the hands of the person being "tested").

I'm surprised at the lack of discussion regarding the Westerfield polygraph.  That may be due to the fact that the case bodes well for polygraph.  According to what I've read, several "suspects" in the case were polygraphed.  Westerfield failed, everyone else passed.  This sounds like more than chance to me.  You can quote lab studies all that you want, but these seem like compelling real world results.  Also, in reviewing the tapes of the polygraph, I found the examiner to be very professional.  He didn't seem anything like the monsters you make examiners out to be.  George I'm curious to hear what you have to say about this.

David Westerfield's taped polygraph and interrogation was released. It should make for interesting analysis since public availability of these are pretty rare. The SDPD should be given credit for taping everything. This also demonstrates an area where the polygraph, even as a prop, can be effective. 

George, if you can get the transcript/tape it should make for excellent site library material. CQT test than can be analyzed in detail including issues such as fear of detection vs fear of consequences - a real problem here for using the poly as more than an interrogation prop.

It is also being reported that the police told Westerfield that he failed with a 99% probability and that all others that had taken the polygraph had passed. This is standard interrogation technique true or not but is being reported uncritically as fact rather than interrogation technique. It is also clear that Westerfield, an accomplished engineer, had no idea how the polygraph works. That's actually a pretty good control question they used since they had info from a sympathetic ex that he had been violent with her once when drunk.

Some of the questions asked are listed.  It was interesting to hear some of the questioning - interrogation in action. He did not confess directly but sounds guilty as hell.

They had to cut the interrogation off once he suggested getting an attorney. Professional job, IMO.

It should also be noted that later, his attorney was in negotiations to tell them where the body was in return for life.

[From the S D Union Tribune]
The test involved Redden reading Westerfield a series of questions in groups of about 10. The questions included, "Is your first name David?" "During the first 45 years of your life, do you remember hurting anyone when you were drunk or angry?" and "Regarding the disappearance of Danielle van Dam, do you know her whereabouts at this time?" 

http://www.signonsandiego.com/news/metro/danielle/20030109-9999_1m9david.html


-Marty