The National Institute of Corrections has published a research study on voice stress analysis (VSA) conducted by the Oklahoma Department of Mental Health and Substance Abuse Services with support from the National Institute of Justice. From the abstract (emphasis added):
…The goal of this study was to test the validity and reliability of two popular VSA programs (LVA [Layered Voice Analysis] and CVSA [Computer Voice Stress Analyzer]) in a “real world” setting. Questions about recent drug use were asked of a random sample of arrestees in a county jail. Their responses and the VSA output were compared to a subsequent urinalysis to determine if the VSA programs could detect deception. Both VSA programs show poor validity – neither program efficiently determined who was being deceptive about recent drug use. The programs were not able to detect deception at a rate any better than chance….
The 128-page report, “Assessing the Validity of Voice Stress Analysis Tools in a Jail Setting” by Kelly R. Damphousse, Laura Pointon, Deidre Upchurch, and Rebecca K. Moore, dated 31 March 2007, may be downloaded from AntiPolygraph.org here (2.1 mb PDF).
I recently went sought employment with a law enforcement agency. I was
given a CVSA. I had done some prior recearch on the CVSA previously, so I
knew this thing was unreliable as a truth or deception device. After
answering the questions that the interviewer asked me, (second time) she
told me that I was being extemely deceptive on just about every pertinent
question! I really came close to becoming argumentativem because the kind
of questions that she said showed deception were just outrageous! But I
held to my guns and told her the TRUTH, that those things were completely
opposite of my character. Well, it turns out that I didn’t get hired. I
don’t know why because it’s against their policy to tell me why! It
really upsets me, because I am well qualified for that job, and would do
a much better job than most of their officers who I have observed over
the years. Anyway, I have applied with another agency and am currently
awaiting word from them. Oh, they use the polygraph! LOL!
I know representatives from VSA, polygraph and all other manufacturers and users of so-called lie detectors read this web site. Therefore, I challenge all manufacturers to pick their most experienced examiners and submit to a high quality and unbiased contest to prove once and for all the accuracy or unreliability of the various truth verification methods.
I know NITV claims better than a 98% accuracy rate, Baker claims a 100% accuracy rate and polygraphers claim accuracy in the high 90 percentage.
I speak with 99.999% certainty that this will never happen. The lie industry abhors hard science.