Great Falls tribune. [volume] (Great Falls, Mont.) 1921-current, 1922-07-08

questioning other persons involved, or
By further detective work. IL is claimed
that the blood pressure tests were in
variably substantiated by the corrob-
orative evidence.
DR.. Marston says that he has always
got 100 per cen satisfactory results
in making the tests himself. That is.
for him the sphygmomanometer has
proved 100 per cent reliable as a de-
tector of deception. Other operators,
less alert to psychological factors in a
case, and less experienced in making
the examinations, have been getting
from so to 100 per cent satisfactory
results.
1t is not a simple matter 70 give a
deception test. From a description of
the method it is readily apparent why
an expert must give it if II is TO be of
any value.
A may have a normal blood
pressure of l20. The sphygmomanO-
meter is fastened to her arm and the
operator listens in.
Whether the first questions are con-
nected with the case or not the sub
jects pressure would probably jump to
40 and remain there. 4 novice might
at once conclude that the subject was
y ~ tHS ms 1utolibIo IutuluH9,
whereas this reaction would probably
be due to a general uneasiness at the
mysterious proceeding. AS the ques-
tons proceed the operator may find
that the chart he is drawing remains
at a level of 100 or drops off toward
normal. indicating that the subject is
truthful in her statements.
Outside influences Noted
the other hand, the pressure NAV
suddenly rise, even reaching a peak
OF 10 or $50 when significant ques-
tons are answered. This would gen
orally indicate a deception curve; not
necessarily. however. To make an ex-
travagant illustration, suppose that
just as an important question is asked
a ferocious gorilla should leap through
the window. This would have nothing
to do with the case, but the subjects
blood pressure would rise to q record
breaking peak.
The tests are given in a room free
from disturbance, but even so the ques-
toner has 10 watch for outside influ-
ence that might affect the chart. In
order to read the chart correctly after
ward each change in pressure must be
marked with its cause.
There is no way of deliberately
tuSdliDS HE UdIoEltltl, inc pSStuplo
gist asserts. 1t might be possible for
a Hindu occult student 10 delay a test
by self -hypnotism. Such persons are
able to slow down the heart action
until it almost stops. and other organs
of the body at the same time are af-
fected. A subject who puts himself
in this state could not be tested until he
released himself. But no one can CON
troll blood pressure alone.
There is one type of individual who
can unconsciously cheat the sphygmom-
snometer. If a person is violently in
sane the test is meaningless. because
such a person has lost consciousness of
right and wrong. Suppore that your
auditory nerve is pressed upon by dis
ease so that you imagine that bells are
ringing constantly. You would truth
fully say that you could hear bells
ringing and our blood pressure would
accept it as a fact. This Is an example
IF a slight hallucination. but it serves
to show how a person with a mind COM
pletely deranged would react to a de-
ception test.
In detectives and slightly insane
cases, the mental and physical func-
tons are subnormal to varying degrees.
Making allowances for this the test
can be used. In drug addicts wen
slighter reaction to questioning is
shown. The chart of an addict will
show curves less than one-third as
great as that of n normal subject.
The blood pressure test has already
proved a friend to the prisoner un-
Justly accused. 1t is the relentless foe
Of the skillful liar. DIR. Marston tells
of a woman who was taken by the