Polygraph Validation Technique - by William Fleisher & Nathan Gordon

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Polygraph Validation Technique (PVT)©; A Case Study

Abstract
This Case Study introduces the Polygraph Validation
Technique (PVT). The PVT is an innovative testing method
to protect against false positive outcomes, while at the
same time assisting the Forensic Psychophysiologist to
overcome denials from deceptive, as later verified,
individuals.

Case Study
The greatest fear of the "Seeker of Truth" is
misidentifying an innocent person as the perpetrator
(False/Positive). With the high accuracy rates of Forensic
Psychophysiology, and the innovations of computerized
systems with algorithms to offer the examiner a second
opinion, there are still times when our conclusions are
suspect.

Perhaps we inform the examinee that the test concerning
the sensitive issue of sexual molestation is over, and
the first thing he says is, "I didn't do it, but every
time I heard her name I could feel my blood pressure
soar!" Or, "I felt a rush of anger that after all these
years my company doesn't trust me, every time you asked
me if I took the missing money."

Obviously, we have to believe in our charts. However, we
are sure there are some cases in the past where you
questioned your own results. There were other instances
where you believed the results were correct, however
failed to confirm them with a confession because you were
unable to overcome the obstacle the examinee presented
with their alternative explanation as to why they failed
the test.

The problem of testing sensitive issues led the authors
to the current hypothesis, which is now being tested. The
PVT is administered in a Peak of Tension (POT) format,
where the issue of each question concerns the cause of an
examinee failing their previous CQT.

A major jewelry store had a series of specific thefts
consisting of five parcels containing loose diamonds and
finished jewelry pieces totaling over $75,000.00. An
initial investigation consisted of Forensic Assessment
Interviews© of six employees, which resulted in a minor
confession by one, allowing us to offer him a polygraph
examination concerning the remaining thefts in accordance
with Federal and State laws.

Procedure
The Lafayette Computerized LX-4000 Polygraph System was
utilized to conduct the polygraph examination. Thoracic
and abdominal breathing, galvanic skin conductance and
cardio-vascular activity were recorded. A known solution
demonstration test was performed, followed by a
multi-issue examination utilizing an Integrated Zone
Comparison Technique format administered over three
charts.

The following pertinent questions were asked in each chart:

C5 During the first 30 years of your life, other than
what you said, did you steal anything else?

R6 Did any relative working at XXX assist you in your
thefts from there?

C8 In your entire life, other than what you said, did
you steal from someone who trusted you?

R9 Other than what you said, did you take any of that
other merchandise missing from XXX?

C11 During the first 30 years of your life, can you
remember stealing anything from a job?

R12 Did you lie in your signed statement (admission of
thefts from XXX) to me today?

The charts were manually scored using the Horizontal
Scoring System and Academy's Algorithm for Manual Chart
Interpretation. Using this system cutoffs for each question,
asked in three charts are a total score of + 4.5. The
examinee's score to R6 was +.75 indicating an Inconclusive
result, R9 was -17.25 indicating a Deception result, and
R12 was -1 indicating an Inconclusive result.

The Lafayette LX-4000 has two internal algorithms. The
John Hopkins University Applied Physics Laboratory
algorithm PolyScore© concluded; Deception Indicated,
Probability of Deception is greater than .99, and the
Objective Scoring System algorithm concluded: Deception
Indicated - Probability of Truthfulness Less Than 6%.

The examinee was informed of his results and maintained
that his relatives who also work for the company told him
that the owners were going to try and blame him for
everything that was ever missing, and this information
caused him great concern when asked about committing other
thefts. Please note a recent inventory was able to
identify specific losses in the range of $240,000.00.

The examinee was instructed to return later for a
re-examination.

Polygraph Validation Technique (PVT)
This examination consisted of the PVT, with the following
questions reviewed in order:

Did you fail your polygraph test because:

1. You were tired?
2. You were afraid I would ask a question I didn't
review?
3. You did not understand all of the test questions?
C4. You lied to a question about theft unrelated to
XXXX?
R5. You lied about your thefts from XXXX?
C6. You were afraid of being accused of XXX thefts you
did not commit?
7. You did not believe the polygraph works?

The examinee was instructed to answer "No" to all of the
questions. Note that although all of the questions dealt
with possible reasons someone may fail an examination,
question C4 & R5 refer to the like questions in the
previous CQT while question C6 refers to the reason the
examinee claims he failed the previous polygraph test .

Theoretically, if in fact the results of the previous
examination were erroneous, and resulted in a
false/positive decision, we would expect that greatest
reaction on the PVT would be when the examinee was
instructed to answer "No" to C6, his actual explanation
of why he failed. Question C4 allows for a second
opportunity to compare the threat of earlier in life
thefts and additional thefts from the ongoing
investigation with R5.

Three charts were administered. The examinee was informed
the first chart would be administered in the order the
questions were reviewed; the second chart would be in
reverse order; and the third chart would be in a mixed
order.

The charts were rank scored using the Johns Hopkins
University Applied Physics Laboratory algorithm
PolyScore©. The algorithm concluded:

The PVT indicated that the greatest reaction was to
question R5, "Did you fail your polygraph test because you
lied about your thefts from XXXX? Question C4, concerning
lying in the first test about earlier in life thefts was
the second greatest reaction, and question C6, where the
examinee was directed to lie to the reason he claimed he
failed the test came in a dismal fourth.

This indicates that the results of the first polygraph
test were valid, and not a false/positive for the reasons
claimed by the examinee. The examinee was shown the
results of the PVT, as well as the charts. He then wrote
and signed a confession for all of the thefts in question.

Conclusion
While still in the experimental stage, the PVT appears to
be an effective testing method of validating prior
deceptive polygraph results. In addition to protecting
against false/positives, it also gives the examiner an
additional tool in overcoming denials and ascertaining
admissions from deceptive suspects.

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