Addiitional comments on the NAS report

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Additional Comments on the NAS report
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One of the major conclusions drawn by the NAS "study"
participants was that many advances have been made in the
polygraph field but that more advances in instrumentation
were necessary because we were using some archaic methods
of monitoring the human physiological systems associated
with polygraphy. Really though, have we made many
significant advances in detecting deception any better
than we did 30 years ago or did the instrument
manufacturers just make things more convenient for us in
the use of the polygraph.

In our November graduation for the Northeast Counterdrug
Training Center Polygraph School, the graduation speech
involved a little "Show & Tell". I displayed to the
graduates and the audience a pneumograph tube from an old
Associated Research (Keeler) polygraph that was in excess
of 40 years old. It was about 1 1/2 feet long and 2 inches
in diameter - the old gas mask tubing. I then displayed a
medium size pneumograph tube distributed by Lafayette in the
early 1970's also made from gas mask tubing, just not as
long or as thick (both tubes still work, however durability
was their best feature). I then followed with a current
pneumograph tube from a computerized polygraph which is
smaller and has more convolutions in the sensor.

The point is that we are still using the same technology as
we did 40 years ago. Instead of the tambour and a lot of
other parts that polygraph students no longer have to learn
(although there is still a vent, it just is no longer a
tire pressure valve), everything has been put into a chip.
But the originating sensor has changed little except in size
and bulkiness. The delivery system is different, but is it
any better at detecting deception?

Fourty years ago, Associated Research and Stoelting had a
hand held galvanometer sensor that was two plates
(electrodes on which to place the ring finger and index
finger) separated by a groove in which to place the middle
finger. It could also be held in the hand. Heavy sweat could
sometimes bridge the groove and complete a circuit between
the two electrodes, bypassing the human body element and
causing the GSR to malfunction. Now we have a more
convenient finger attachment. The same technology that we
had when I bought my first polygraph in 1972 from Walter
Van De Werken. Again, the delivery system is now in a chip,
but the originating sensor remains the same. Is it any more
accurate than what we had 40 years ago?

The cardiosphygmograph, like the pneumograph, has had its
delivery system integrated into a chip, but the
originating sensor technology remains the same (except
there is no longer a vent). Is it anymore accurate that what
we had in the past?

Obviously, with the electronically enhanced systems
developed by Lafayette and the electronic systems developed
by Stoelting, they were more convenient for the examinee
because "cuff" pressure was no longer an issue, but detail
was lost and accuracy may have been lessened.

The argument that, "Hey we are computerized, now", is not
convincing to those who had to learn and understand the
instrumentation technology while in polygraph school. The
computer is smaller, more convenient to transport and set
up. In terms of test convenience, it is fantastic, but
is the accuracy any better than that of the properly
functioning analog?

Then, of course, there is the argument, "Well, hey, the
computer has scoring algorithms so that makes us more
accurate". The scoring algorithms are helpful, sometimes,
like when they agree with our handscore. However, what
happens when they don't agree? We start to second-guess
ourselves then when the computer "sees" things we don't
see.

One of the biggest "downsides" of the scoring algorithms
is that polygraphists who were incompetent at test data
analysis were given new life when scoring programs were
developed. They are still incompetent, but now they have
documentation to show how the examinee did on the
examination. Of course, APA and ASTM (and I think AAPP)
have rules and standards that prohibit test results to be
based solely on a computer score. But hey, every state has
rules against murder, rape, robbery, etc. which have much
greater consequences for violation, but that doesn't stop
the violators.

One of the new instrument manufacturers, Limestone
Technologies of Canada, has indicated in their marketing
literature that they have a skin temperature sensor to
monitor it during an examination. A polygraphist that was
considering purchasing one was discussing this with me.
My response was basically, "So what". I was not being
this way to have an offensive attitude, but rather, as
I explained to him, what information and research do they
have that indicates that skin temperature of the human
extremities has any relevance at all to deception
detection. John Reid used a skin temperature sensor many
years ago, but it evidently had no relevancy or other
manufacturers would have been using it after John Reid
did. Limestone also has the technology, according to the
person with whom I was discussing this, to monitor
dilation and contraction of the eye pupils with a face
mask device. What research exists that indicates that this
means anything in the detection of deception? Someday,
these may be a standard part of polygraph technology and
make our examinations more accurate.

In Israel, back in the early 1970's, a methodology was
being developed to monitor respiratory activity with a
microwave beam. They made a presentation on this at one
of the APA seminars and were having, as I recall,
excellent results and more accurate respiratory readings.

The key here, obviously, is the accuracy part. I have
read or heard little about this since that time. I would
imagine that the cost and ability to build the
technology into a portable polygraph was prohibitive.
Likewise, some readers may be aware of the Vericator,
whose developers are working with the polygraph field to
find a way integrate their technology, non-verbal
behavioral indicators and voice stress, with polygraphy.

We have also been informed at seminars about the use of
brain scans and thermal imaging for deception detection;
however, like the Israeli microwave respiration monitor
and the Vericator, cost, integration ability, and
portability may be factors which make their use
impossible.

In summary, the NAS report was correct in that we do
need new technology and new sensing devices validated
in being able to monitor human psychophysiological
responses in the quest to detect deception more
accurately. How this can become a reality where we can
have practical and effective use, is an entirely
different debate. I think I'll be retired by then and
probably won't really care, but, hopefully, it will
happen sooner than that or the survival of our profession
will be in jeopardy.

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