00 wrote on Sep 11^th, 2001 at 6:10am:


Polygrapher James Allen Matte writes at p. 383 of Forensic Psychophysiology Using the Polygraph (J.A.M. Publications, 1996):

Quote:


Note that effective polygraph countermeasures involve augmenting physiological responses to the so-called "control" questions rather than suppressing responses to relevant questions. See Chapter 4 of The Lie Behind the Lie Detector and the sources cited there for further reading.

I would expect that if there were no GSR responces at all the examiner would suspect either that the polygraph equipment was not operating properly, or that the examinee were using some sort of chemical countermeasure. either way you'll lose.
I am not an expert, but common sense would tell me that something was wrong, (besides the fact that polygraph is hokey anyway), if there were no readings at all.

Add:Testing with a biofeedback unit shows virtually no response change from sedate to excited states.


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naut x naut west

Thank you.  The question is directed at the use of a certain chemical which locally supresses all sweat gland activity.   
Is the finger inspection strictly by inspection, is it by wiping the fingers to clean them, or possibly a swipe test for any chemical agent?

What would an examiner likely do or suspect if there is no GSR response?


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naut x naut west

00 wrote on Sep 11^th, 2001 at 6:10am:


Polygraphers routinely check the examinee's fingertips for anything that may affect "good" contact with the skin. Mostly this would be superglue or other adhesive material that blocks the contact. As far as other "chemicals", I do not know what if anything a polygrapher would look for (as far as the GSR goes).

I would think, and this may be completely wrong, but I feel that if the examinee is comfortable with his or her knowledge of the polygraph and it's shortcomings the GSR would be less reactive? Confidence would have to have some affect I would think.

Anyone agree?

00 wrote on Sep 11^th, 2001 at 6:10am:


Both 'The Lie Behind The Lie Detector' and 'How To Sting The Polygraph' suggest that such attempts do more harm than good, or are at least ineffective.

I too would like a good GSR discussion as it seems to be the one tracing in which the examinee has little or no control.

Regarding the attachment of the electrodes / conductors for the GSR:

Does anyone have any experience with examiners checking or cleaning the fingers prior to attachment? 

Have you ever heard of this?

Would they likely discover a chemical agent that supresses sweat gland activity (well beyond anti-perspirant)?

Would that do any good?


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naut x naut west