You
The Myth About
Scientific
Lie Detectors
This suspect. wearing the
head-type contact, answers
police. But can we rely on
the verdict of the lie detector?
DID YOU KILL HER?
' 'They're just a form of psychological rubber hose," says the author,
"but they're applied with subtlety instead of the usual brutality."
By Robert Hertzberg
After undergoing a Lie-detector test
at police headquarters, Joe McGlook,
37, no home, signed a confession last
night admitting his participation in the
fatal hold-up several days ago of a
gas station attendant on River Road.
1
TEMS like that appear frequently in
daily newspapers and cause many
people to wonder. How do lie detectors
work? Do they really work at all?
Clear away the aura built up around
these gadgets by imaginative fiction writers
and hard-working police departments and
the uncharitable but undeniable answer is:
Lie detectors usually don't detect anything.
At best, they are a form of psychological
rubber hose, applied with subtlety rather
than brutality, but a form of coercion
January, 1950
nevertheless. With their assistance, police
can sometimes sweat a confession out of a
suspect and there are no incriminating
bruises left on the victim for the indignant
defense counsel to display to judge and
jury.
The expression "sweat a confession" is
employed in its literal sense and not merely
as a figure of speech. Use the daintier
word "perspiration" if you like, but what-
ever you call it, it plays a very important
part in the operation of lie detectors.
Stripped of extraneous knobs, dials and
flashing lights best dismissed as eye wash,
the usual lie detector is essentially a radio
ohmmeter. An ohmmeter is a very simple
device that measures electrical resistance,
the unit of which is the ohm. From your
high-school physics you may dimly recall
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modernmechanix.com