TRUTH AND CONSEQUENCESpolygraph operator hits an emotional response, the machine will
register it. The emotional response, however, may have nothing
to do with lying.
Take the example of a teller being questioned because his or
her drawer shows a shortage of five hundred dollars. The operator
will start by asking innocuous questions. "Do you live in town?"
"Are you married?" "Is this Monday?" And then the casual question
is inserted: "Did you embezzle the five hundred dollars?" If the
polygraph records emotional arousal at this point, the teller's "No!"
can be considered a lie. The obvious flaw is that in all probability
any reference to the money will cause an emotional reaction.
The other flaw in polygraph testing comes when the person
being questioned is an accomplished liar who has learned to control
his or her emotional response—and many people can do that.
Another problem is the liar who believes the lie. No amount of
testing will shake him or her, because in that person's mind it is
not a lie.THE LYING NURSES
If there are no specific facial or body subtexts to lying, how
are we to tell a lie from the truth? Can we? Well, not always,
but sometimes we can. There are times when we are absolutely
certain that someone is lying, and those are times when the lie
is tied to a strong emotion. In a sense, we act as the polygraph
does. We link the sudden emotion to the statement, and our inner
self cries out "A lie!"
The face is a reliable index to many basic emotions. Dr. Paul
Ekman, a professor of psychology at the University of California
in San Francisco, conducted a study to find out if the face can
give clues to when someone is lying.