The Topeka state journal. [volume] (Topeka, Kansas) 1892-1980, 1922-07-08
TOPEKA STATE JOURNAL
Information Bureau
FREDERIC J. HASKIN. Director.
Washington. d. o.
LIARS AND BLOOD PRESSURE

day every prisoner at Ine OAR SihdJ
have his story scientifically tested for
truthfulness. Blood pressure has been
tried and proved as a gauge Of decep-
ton, and a method has been evolved
by which an expert can test with rea-
sonable exactness the truth of the
spoken word.
Thus a prisoner may recount calmly
a plausible alibi for a crime Perhaps
he shows no visible symptoms of fear
or nervousness. But If he is not
telling the truth his blood pressure,
over which he has no control, is re-
acting violently to the fear OF dis
covery. On the other hand, If he is
telling the truth however fantastic,
his blood pressure will bear him out
by remaining at a comparatively nor
NAL level.
The blood pressure deception test
has been developed to practical
stage. 1t was used by the department.
of justice in connection with wartime
spy cases. 1t is being used now by
criminologist of the Berkeley, Cali
fornia, police department.
Here in washington the man who
developed the test has just tried it on
a negro accused of murder. Evidence
is against the suspect, but the test in
dicates that his alibi is correct. He
is now being held while other sus-
poets are being trailed.
This illustrates the place which the
deception test will probably come to
hold in criminal investigation. 1t Will
not be taken as absolute PROOF of
where the evidence would convict a
man in spite of his plea of innocence
the deception test may lead to a fur
Their inquiry into other clues. With
the test in use railroading a man to
Jail may be no longer a frequent &C.
currence.
The pioneer of the blood pressure
deception test is DIR. William NJ. Mars
ton, professor of psychology at tho
American university. DIR. Marston
says that there has been some misun
Outstanding about his work. He uses
three different kinds of deception tests
of which the blood pressure test is the
most reliable. All of the instruments
adapted for use in giving the tests
were invented some time ago for
various purposes. DIR. >Marston ex-
plains that he is the inventor of the
blood pressure test, but not of tho
instrument.
The Deceptive Complex.
Working at the Harvard laboratory
in 1913, he evolved the theory that
blood pressure is an indicator of de-
ception. Fear and anger largely con-
stitute the deceptive complex, and
these are the only emotions that in
fluence to any extent systoltc blood
pressure on which the tests are based.
DIR. Marston found by experiments
that If anyone attempts to deceive the
emotion of fear influences his blood
pressure in definite ways. Even if the
possibility of detection is remote the
organs respond somewhat to an in
herent fear. 1t is not normal to lie
and this departure from normal has
its reaction In the blood pressure.
Using an instrument which is at
tached to the arm, and which he calls
a sphygmomGnometer, the psycholo-
gist made numerous tests which suS-
tanned his theories. Tests were made
of persons held by the police depart
ment for theft, drug-taking, proSti-
tuition, forgery and bootlegging. After
each test was made DR.. Marston- gave
his verdict as to the truth or falsity
of the subjects account. Then the
investigation was continued by med
ical examination, questioning other
persons involved, or by further detec-
tive work. 1t is claimed that the
blood pressure tests were invariably
substantiated by the corroborative evil
dence.
Dr. Marston says that he has al
ways got 100 per cent satisfactory re-
suits in making the tests himself. That
has proved 100 per cent reliable as n
detector of deception. Other oper-
ators, less alert to psychological fac
tors in a case, and less experienced
in making the examinations, have been
getting from 50 to 100 per cent sat
isfactory results.
1t is not n simple matter to give a
deception test. From a description of
the method it is readily apparent why
an expert must give it If it is to be of
any value.
A woman may have a normal blood
pressure of 40. The sphygmoman-
ometer is fastened to her arm and the
operator listens in. Whether the first
questions are connected with the case
or not the subjects pressure would
mr. nIQfl Al 1rTrV1 n q in
there. A novice might at once con-
clude that the subject was not an
swering his questions truthfully.
where 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 $50 or drops off toward
normal, indicating that the subject Is
truthful in her statements.
Outside Influences Noted.
On the other hand. the pressure
may suddenly rise, even reaching a
peak of ITO or $50 when significant
questions are answered. This would
generally intricate a deception curve;
not necessarily, however. To make
an extravagant illustration, suppose
that just as an important question is
asked a ferocious gorilla should leap
thru the window. This would have
nothing to do with the case, but the
SuDJecCS DlO0d pressure would rise TO
a reeord-brea king peak.
The tests are given in a room free
from disturbance, but even SO the
Questioner has to watch for outside
influences that might affect the chart.
In order to read the chart correcly
aferward each change in pressure
must be NAKED with its cause.
There is no way of deliberately
cheating his barometer, the psycholo-
gist asserts. 1t might be possible for
a Hindu occult student to delay a
test by self-hypnotism. Such persons
are able to slow down the heart ac-
ton until it almost stops, and other
organs of the body at the same time
are affected. A subject who put him
self in this state could not be tested
until he released himself. But no