The Lie Behind the Lie Detector

[George Maschke]

The 3rd edition of AntiPolygraph.org's free e-book, The Lie Behind the Lie Detector, is now on-line and may be downloaded as a 1 mb PDF file here:

http://antipolygraph.org/lie-behind-the-lie-detector.pdf

This new, revised and expanded edition includes updated chapters on polygraph validity, policy, and procedure, as well as information on how to protect oneself against a false positive outcome.

It will be of interest to any who may some day be asked or required to have a seance with a polygraph soothsayer.

[davefoc]

Suppose that the use of a polygraph and its output are useless to determine whether a person is telling the truth or not.

But suppose, by maintaining the big lie that polygraphs work police are able to trick criminals in to revealing information that they would not otherwise including the inducement of confessions not otherwise obtainable.

Is the enough to justify the polygraph big lie?

Is the ability of a polygraph examiner to discriminate between truth and untruth in a subject that doesn't believe that polygraphs work greater than his ability to discriminate between truth and untruth in a subject without the use of the polygraph?

[Sundog]

Originally posted by davefoc
Suppose that the use of a polygraph and its output are useless to determine whether a person is telling the truth or not.

But suppose, by maintaining the big lie that polygraphs work police are able to trick criminals in to revealing information that they would not otherwise including the inducement of confessions not otherwise obtainable.

Is the enough to justify the polygraph big lie?


:eek:

Sure. To heck with all those people whose lives it ruins, if it gives the cops more information.

Sheesh. Time to call it a day...

[arcticpenguin]

Originally posted by davefoc
Suppose that the use of a polygraph and its output are useless to determine whether a person is telling the truth or not.

But suppose, by maintaining the big lie that polygraphs work police are able to trick criminals in to revealing information that they would not otherwise including the inducement of confessions not otherwise obtainable.

Is the enough to justify the polygraph big lie?

Is the ability of a polygraph examiner to discriminate between truth and untruth in a subject that doesn't believe that polygraphs work greater than his ability to discriminate between truth and untruth in a subject without the use of the polygraph?
Sounds a bit like "if she was a witch she wouldn't drown" to me.

[tracer]

But without the polygraph, what would they ever have used in such Earth-shatteringly important television series as Anything for Love or Who Wants to Marry My Dad?

[SquishyDave]

Originally posted by tracer
But without the polygraph, what would they ever have used in such Earth-shatteringly important television series as Anything for Love or Who Wants to Marry My Dad?
I think we had a similar show called meet my folks or some such, in which parents had 3 guys come to their house for a while and then subject them to whatever tests they want, culminating in a polygraph test, then the parents decided which of they guys they would pimp their teenage daughter out too.

Yeah I love lie detecter tests.

Originally posted by davefoc
Suppose that the use of a polygraph and its output are useless to determine whether a person is telling the truth or not.

But suppose, by maintaining the big lie that polygraphs work police are able to trick criminals in to revealing information that they would not otherwise including the inducement of confessions not otherwise obtainable.

Is the enough to justify the polygraph big lie?

No, they use polygraphs for job interviews in the states don't they? It has been shown to not work, so why use it? You can always torture the criminals to get info out of them. And in the end, finding out where someones stereo has been stashed hardly counts enough towards perpetuating a lie. A lie that has huge negative consequences.

[ManfredVonRichthoffen]

Originally posted by davefoc
Is the enough to justify the polygraph big lie?


They return lots of false positives. Meaning it says you are lying when you are not. If the polygraph big lie exists, then the person who is innocent must start his defense by proving that the polygraph is bullsh1t. Not the place one would want to start.

Somewhat like cop intuition, believe of guilt or innocense by the examiner of the examinee influences the result. To me this implies that a racist examiner will be more likely to find a minority examinee guilty.

[Ladewig]

Is it still true that no U.S. government agency has ever caught a double agent using a polygraph?

[Tony]

Originally posted by Sundog


:eek:

Sure. To heck with all those people whose lives it ruins, if it gives the cops more information.

Sheesh. Time to call it a day...

We agree again!! :roll:

I have always been suspicious of polygraphs, how does it know im not really nervous?

[ManfredVonRichthoffen]

From the book:

In 1986, I was privy to a drama staged by the producers of CBS
TV’s news program, “60 Minutes,” that investigated the contro-versial
use of polygraph tests by private employers. My initiation
into the lie detector conflagration was the unintended outcome
of an assignment from the Congressional Office of Technology
Assessment to examine the validity of polygraph tests…. The “60
Minutes” staff sought my help as they designed a demonstration
of the use of polygraph tests. What resulted was an elaborate
deception experiment that would have been the envy of 1960s
social psychologists.
Using CBS-owned Popular Photography magazine as a front,
“60 Minutes” hired several polygraphers to identify the culprit in
an alleged theft. The design was quite sophisticated: CBS randomly
selected four polygraph examiners from the telephone directory
and had each polygrapher examine four employee suspects. The
polygraphers were initially contacted by a manager at the magazine,
who told them that more than $500 of camera equipment had
been stolen, almost definitely by someone on the inside. The
polygraphers did not know that other examiners had been engaged,
and they conducted their examinations in a Popular Photography
office. Unbeknownst to them, the office had been modified to
enable surreptitious filming. When the polygraphers arrived on-scene,
each was told that although all of the suspects had access
to the camera, one of the four was probably the guilty party. A
different person was “fingered” for each polygrapher.
Not surprising to polygraph critics, each examiner found the
person who had been fingered to be deceptive, and each examiner
tried mightily to get the guilty person to confess. No one, of
course, had stolen anything. The four employees were confederates,
paid $50 if they could convince the polygrapher of their innocence.
With dramatic flair, CBS demonstrated that polygraphers do not
necessarily use psychophysiological information to make their
diagnoses of deception.


Crap. Can't believe my wife will probably end up taking these.

[ManfredVonRichthoffen]

One area of special concern in personnel security screening is the
incorrect identification of innocent persons as deceptive. All other
factors being equal, the low base rates of guilt in screening situations
would lead to high false positive rates, even assuming very high
polygraph validity. For example, a typical polygraph screening
situation might involve a base rate of guilt of one guilty person
(e.g., one person engaging in unauthorized disclosure) out of
1,000 employees. Assuming that the polygraph is 95 percent valid,
then the one guilty person would be identified as deceptive but
so would 50 innocent persons. The predictive validity would be
about 2 percent. Even if 99 percent polygraph validity is assumed,
there would still be 10 false positives for every correct detection.

Ugh

[nightwind]

Interesting comments on the polygraph.

Any ideas about the penile plethysmograph and its reliability?:p

[George Maschke]

Originally posted by nightwind
Interesting comments on the polygraph.

Any ideas about the penile plethysmograph and its reliability?:p

This supposed test for sexual deviancy seems to be pseudoscientific quackery, too.