TN_Cop wrote on Dec 27^th, 2004 at 10:56pm:



You are quite wrong in that statement, sir.  The CVSA frequency analysis is only going to be as accurate/sensitive as the microphone being used.  I can tell you as a statement of fact that no lavalier mic has a frequency range beyond 15Hz to 20kHz.   

The average human hearing range is 20Hz to 20 kHz.  Therefore, any frequencies that a lavalier mic and detect, a human can detect as well.  Also, the lav mics being used with a CVSA are no different than the ones that can be found in a musical instrument shop or high-end recording facility.   

I know this , because I work in the audio industry as an audio engineer and I can tell you that, as an expert in audio with a BS in audio engineering and another in psychoacoustics (yes, that is an actual field of study), there is absolutley NO way that a CVSA or any other machine can detect lies or deception by recording the waveform of a human voice.   

I work daily with audio software and hardware that well exceed $200,000.  I have done forensic audio reconstruction for police departments in the past, I can isolate a voice from background noise, I can manipulate speech so a male sounds like a female (not as simple as changing the pitch, either), I can look at a waveform of a human voice and tell you its frequency range (FM) and also its gain (AM) down to the sample level (very accurate) and there is no way in hell that one can detect deception!   

So, do you actually think that a piddly machine that costs $10,000 (the price of one vintage Neve preamp, used for record audio) can detect deception?  Hah!  I'm more capable of detecting deception with the equipment that I use than a CVSA is capable of doing! When I tell my fellow colleauges about the CVSA, I consistantly get smirks and laughs from them, because they know as well as I do that the CVSA is a joke.  So, please don't insult my intelligence and that of everyone else here by trying to explain the "science" of the CVSA.  Bah!

well this is funny.
you wont belive it.
i just got my letter in the mail, from the state.
telling me that i passed their background check and interview....now i am in pool of people waiting to get hired....

TN_Cop wrote on Dec 27^th, 2004 at 10:56pm:


I did not "admit" that I "don't know anything" about CVSA. You had only asked whether I was certified as a CVSA examiner. The fact that I'm not doesn't mean I don't know anything about CVSA.

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The claim that CVSA can detect stress has yet to be proven through peer-reviewed scientific research (as does the claim that stress is diagnostic of deception).

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The patterns are easy enough to read. From the NITV website, in a page whose title includes the claim that they are "Lie Detection Experts":

 

So, a pointy spike like an inverted "V" means that the person is telling the truth, and a flattened top, shaped more like an inverted "U," means the person is lying. (Almost as easy as reading a Magic 8-Ball.) And even if the qualified examiner has difficulty reading it, the computer can do it for him.

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It's good that you acknowledge that the CVSA is not a lie detector, as NITV did in court. Yet as we have seen, on their website, NITV claim to be "lie detection experts" and purport to show how to tell a truthful response from a lie.

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Not necessarily. Especially considering those making decisions to spend taxpayer money on the device are being misinformed by NITV about the device's capabilities.

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I understand psychophysiologist Dr. David T. Lykken's conclusions regarding voice stress analysis, which are based on a review of the research literature. He devotes a chapter of the 2nd edition of his seminal treatise, A Tremor in the Blood: Uses and Abuses of the Lie Detector, (Plenum Trade, 1998) to voice stress analysis. He concludes:

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You also ask:

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Yes. A friend of mine who is a certified CVSA examiner (and understands full well that the "test" is completely bogus) administered a CVSA examination to me to familiarize me with the procedure.

I also had the opportunity to do a little test of my own. I simply said "no" into the microphone in a normal speaking voice, and not in response to any questions. I was quite relaxed. The situation was not stressful. But about 1/3 of the time, the CVSA said that I was being deceptive!

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I think I'll pass. I already have a copy of the CVSA operator's manual, which I have read.

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Somehow, I suspect you did not know my responses before I typed them.

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Again, I think I've done my homework on the CVSA. Could you point me to any peer-reviewed research that supports the manufacturer's claims? For example, NITV marketing materials have claimed that the device has "an accuracy rate of 98%."

CVSA operators are taught to make similar claims about CVSA to those whom they "test." The following is straight out of the CVSA operator's manual:

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Where's the proof that CVSA has an accuracy rate on the order of 98%?

Jeffery-

Your right, anyone in their right mind would be stressed about having to take any type of test relating to pre- employment or criminal activity.  There are measures that are built in to detect situational stress and stress relating to specific questions asked.  Its a pretty cool machine that is a great tool in ASSISTING with the interview or interrogation of subjects.  You shouldn’t be fired, not hired or charged with a criminal offense just based on the results of the test alone.  Its what comes out of the pre interview and post interview that will get you.   

The 60 hour course to become certified wasn’t a joke, it was pretty hard to understand at first.  Its not rocket science and its a pretty easy thing to grasp once you get the hang of it.  Other interview and interrogation courses should be made pre requisites before obtaining certification to administer the CVSA, I would recommend the John E. Reid interview and interrogation school.

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Its not my opinion that its either deceptive or non-deceptive, its the way they teach the course and the way you read the charts.  There is no in the middle.  Its either DI or NDI.

County26-

One would think the test results would be made available to you through open records act.  The problem I see is there are so many widely ranging policies and procedures about what to keep and what to destroy after the test; I bet they differ from agency to agency.  I keep all charts, copies of questions, and after test reports in case anything comes up at a later date. 

George-

I read your "Too Hot of a Potato: A Citizen-Soldier's Encounter with the Polygraph" and I appreciate all you did for our country.  It seems you got the raw end of the stick when it came down to that guy and his polygraph.  I am not versed in the ins and outs of the polygraph so I don’t have much to base any opinions on but it does seem unfair in your situation.  I cant believe you didn’t seek some type of legal action over the obvious slander and life altering actions it caused.


TN Cop

"inconclusive"

makes me think he lied about my test.

thats why i had to take it over and over again.

cause if i was guilty then i would of been arrested on the spot.

but come on now....if a CVSA is a stress test then i should of not taken it cause i was stressed from losing my day job the same day i was told to take the CVSA.
so my stress factory was about the same as Saddam's when they pulled him out of that hole in the ground.

TN Cop-

Any machine used to make critically important life altering decisions where the operator can be qualified after only 60 hours of training is a BS machine with little more acuracy than a crystal ball.  Great.  You can measure voice stress.  Guess what -- if I am hooked up to a machine (or no one is being used) that I know will measure me and the results of that measurement can have career impacting results, I'm going to be stressed.

Obviously these machines aren't fool proof.  As evidenced by county26's vindication after being judged "inconclusive" which you state shouldn't even be an option with CVSA.

Your four year old must either be really smart, or there isn't much to these 'tests' and the standards for those who administer them are pretty low.

do you think i can get a copy?
it would be nice...

County-26-

You should be mad, and I don’t blame you for wanting to do what you can to get your revenge.  If you get copies of the CVSA tests you can contact me through this site and I will give you a cold call and explain what your looking at.

George-

The more you write and the more I read it seems like your that kid in the fourth grade who didn’t get his way on the basketball court and is crying foul to anyone who will listen.  Before you bash something you admittedly know nothing about go and take the CVSA or polygraph course and become an examiner yourself.  Then and only then will you have any basic knowledge to base your beliefs on.   

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The CVSA is based on the scientific fact that it can detect certain FM frequencies that are not heard by the human ear.  The spoken voice that you hear when someone talks to you is AM frequencies and it is carried on FM frequencies.  When someone is stressed the vocal cords and the voice box tightens and the FM frequencies are changed and the change isn’t detectable by the human ear.  The CVSA does detect that change and it shows during the test.  Then a qualified examiner who knows how to read the patterns can interview and interrogate the tested based on the questions they showed stress on.  Like I have said many times before the CVSA is not a lie detector, it only detects stress reflected in certain patterns.  Obviously the government agencies that buy the machines are having tremendous success at what they do or they wouldn’t spend the money at all.  I don’t seem to understand why you cant comprehend what the CVSA does, even my four year old understands and can pick out the stressed voice patterns on the test.  Have you ever even seen or been subjected to a CVSA examination?

Seriously, go and take a CVSA course and become a certified examiner.  It will take about 60 hours of your time and then you can bash rant and rave all you want and I will take your more seriously.  I know your responses before you even type them.  Its the same every time and it gets old hearing the same old thing and the same old quotes.  Try something original and get a thought of your own and then share it with the group.

I’m sorry about your experiences with the FBI polygraph examination.  I know its a bitch when one is falsely accused of doing or being something they are not.  Just because you had a bad experience with the polygraph don’t bash the CVSA until you have some experience with the machine and what it can do.

Thanks,
TN Cop

If you don't plan on working at that county again (and if your current county won't mind ** think about this seriously first ** ) then you may want to expose the fraud you experienced publicly.  A call to the local newspaper /TV Station tellng then you were "forced to resign after being accused of failing a CVSA" and then vindicated when the real crook was caught would be eye opening and interesting.  It's awfully nice (sarcasm) of the old sherriff to give you a good recomendation after their flawed system reuined your job.

As others state, you may want to engage a lawyer before doing anything else; but they messed with you; you have now been vindicated.  Time for some revenge.  Make them (especially their CVSA examiner who tried to manipulate the CVSA test results to what they wanted) look really bad.

TN_Cop wrote on Dec 26^th, 2004 at 8:17pm:

i was just thinking about this....
There is no inconclusive tests concerning the CVSA, they are either deceptive or non deceptive.
so that either means that the test was non deceptive (cause they found out who took the money).
and or they were trying to get a negative result.
cause i looked guilty as hell.
now i am getting really pissed. i am half temped to publish where and when i took the test. maybe i am not the only one who got screwed over by this guy.
He told me that he has been a tester for many years...
he told me how many test he has given...i think it was like 4,000...but dont quote that...it was alot....
i am wondering if the tester is just a dork.
i hope that the gal that stole all that money from the jail gets hers....

TN Cop,

You write among other things:
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People get screwed not just because of examiner incompetence, but because the exam itself is without validity. The "National Institute of Truth Verification" (NITV) and the community of CVSA operators are complicit in promoting public belief in a lie (the notion that CVSA can detect deception). How many CVSA devices would NITV be able to sell to government agencies at $10,000-a-pop if they were to honestly explain that CVSA can neither detect deception nor "verify the truth" and in fact has no scientific basis at all? How many city councils would approve the expenditure of taxpayer dollars for CVSA devices and training if the public safety officers who sought them were to truthfully explain that the device is no more accurate than a coin toss?

I am neither a CVSA nor a polygraph operator. I'm just a concerned citizen. My concerns about lie detection (and discovery that it is a fraud) began when I was falsely accused of deception during an FBI pre-employment polygraph examination. For an account of that experience, see my statement, "Too Hot of a Potato: A Citizen-Soldier's Encounter with the Polygraph."

George,

Thats just the way the tests are classified, "deceptive" or "non-deceptive".  The point being there isnt a classification for a CVSA test as being "inconclusive"  Its not a lie detector and you can show deceptive with the CVSA without lying.  Hell you can classify the tests "stressed" or "non-stressed" and its still a useful tool and does the same thing.

It amazes me how much hatred you have towards these machines and their uses.  Sure some people get screwed because some of the examiners dont know how to affectivly use the tools but I would bet more times than not these machines are used to illicit confessions and admissions from very undersirable people who have commited the crime or have done whatever they are accused of doing.

I have one more questions, are you certified as an examiner in either the CVSA or the polygraph?  Did you or someone you love fail one of these tests and it change your life?  I am curious to know where your hatred comes from.

Thanks,
TN Cop

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This would be much appreciated. External links (the number of Websites that find a particular site worthy of a link) influence Google rankings tremendously. If you could link the home page (instead of the message board), it would go a long way toward helping us keep our #1 ranking.

Thanks again, and all the best in the New Year.

sound  like a good idea. i will put a link on my website for this board. i am active in alot of stuff on the net...and i get alot of hits.
if this county here requires a test i will simply quit.
the whole thing makes me sick.

Unfortunately, it seems that governmental reliance on lie detectors is growing, rather than shrinking, despite the overwhelmingly negative recent findings of the National Academy of Sciences in its report, The Polygraph and Lie Detection, which also addresses voice stress analyzers. Depending on where you live, you might have little choice about whether or not to submit to a lie detector test if you want to work in public safety.

I hope you might consider helping us to spread the word about lie detectors to others before they become victims. For example, if you participate in any other message boards, please consider mentioning the information available here (it's all free) if the subject of lie detectors comes up. For additional ideas, see our Get Involved page.

If we are to put an end to misplaced governmental reliance on lie detectors, we need to make those who are subject to it aware that it's a fraud.

up untill now i never had anything to hide.
however i will never take one again, either the polly or cvsa.
i will get the book, to read....just for my info...
thanks for the post...i wish i would of found this site along time ago...

I'm sorry that unfounded suspicion based on an invalid test has had such a disruptive impact on your life. I hope your local county doesn't require one to pass a "lie detector" test (whether CVSA or the polygraph) as a condition of employment. If it does, see The Lie Behind the Lie Detector for tips on how to pass. Although this e-book does not directly address CVSA, the "behavioral countermeasures" presented in Chapter 4 will be helpful in any interview/interrogation.

yes they probably would rehire me, however i had moved 300 miles to get the job with the county and when stuff hit the fan i moved back to my original place.
i don't feel like relocating again. i am currently trying to acquire a position with the local county.

county26,

I'm glad you were able to obtain a favorable letter of reference from the sheriff, and wish you all the best in finding  the job of your choice. Under the circumstances, shouldn't you be eligible for re-hire by the county?

i could of pushed it i guess....however like i said i was never so stressed as i was....in my entire life...i lost one dream job then lost my other dream job...working for the county....yea it was just as a jailer...but i loved my job...
now the whole county knows the truth...
they were audited by the state....

county26,

It is to be hoped that the sheriff has also learned how stupid it is to rely on the results of a CVSA "test." He might just as well have consulted a Magic 8-Ball.

TN Cop,

Don't you see the contradiction between your statement that CVSA results are either "deceptive" or "non-deceptive" and your admission that CVSA is not capable of lie detection?

???

hmm thanks for the info...
its water under the bridge now...
the sheriff wrote me a great letter of reference.

1.  You cant lose your job because of the failure of a CVSA test, seek a lawyer.

2.  There is no inconclusive tests concerning the CVSA, they are either deceptive or non deceptive.  Seek a lawyer.

3.  The CVSA tests are only as good as the operator and its only a tool to assist in the interview of subjects.

4.  Before George W. Maschke our especially senior user has the chance to say it I will, CVSA is not capable of lie detection.  It, as so named, is a voice stress analyzer which is just another tool for the interviewers.

Sorry about your luck
TN Cop

its a long story a sad story. i worked for a county as a jailer at night. there was some monies (120.00) stolen from a suspect i had booked in.
i was told that if i took the CVSA it would clear my name.
it just happens that that day, i lost my day job that payed very well. i told them that i never been so stressed in my life, as i was at that point.
don't worry, i was told just do the test and you will be cleared.
i went down to take the test. i had to do a trial test, then the real thing. no go....so i had to take it again.no go again.
at this point i was really freaked out. so they gave me the option of taking the test the next day.
i did a "trial" test that was fine...then the real test...no go.
the tester told me that "the test was inconclusive"
so i was forced to resign from the department. 
that was in March 2004, then in October 2004 it turns out they found the person who stole the money! she made off with like 15,000.00
i have no faith in these things and the more i read about them...i doubt them even more.