We've all seen it in the movies some cops are digging for the truth the perps insist you
can't handle the truth and bam they break out the polygraph machine according to tv
the polygraph is a fail-safe way to get to the truth and find out when someone is lying
but in real life they fail to live up to the hype the lie detector would be better suited
as a fear detector that's because so-called lie detection involves inferring deception
through analysis of physiological responses to a series of questions the only problem
with that there's no recognized set of physiological responses that indicate deception
an innocent person could be nervous over being questioned and a sociopath could be as cool as
a cucumber as a result they're inadmissible as evidence in most federal and state courts
but still just because lie detectors are junk science doesn't mean you can't learn to beat
them to beat a lie detector test you first need to understand how they work they typically monitor
three indicators of human behavior heart rate and blood pressure respiration and skin conductivity
when you're taking a polygraph test the machine first registers the baseline of your vital signs
examiners then try to trick you into lying by asking you a series of controlled questions that
are only distantly related to the crime they're actually investigating questions like did you
ever lie to get out of trouble or have you ever committed a crime most suspects will answer no
to these types of questions since they're trying to come across as an honest and trustworthy person
but examiners assume that the answer to at least one of these control questions will really be a
yes after all you've probably lied at some point or another and when they're asking you if you've
ever committed a crime the time when you were 12 and jaywalked will suddenly start replying in your
mind as soon as the suspect tells one of these white lies it puts a blip on the polygraph machine
that serves as an example of the physiological response given when the suspect lies mixed in with
the control questions are relevant questions in a drug case for example a test conductor will ask
did you ever use an illegal drug the conductor scores the test by comparing the physiological
responses to these relevant questions against the probable lie questions if you react more strongly
to the relevant questions they'll say you're lying but if you're truly innocent you should fear the
control questions about your past more and thus react more strongly to them from this they'll
conclude you're telling the truth or at least that's how the theory works by knowing how the
machine works you can beat it by lying just as much with your body as you are with your words
remember a suspect's lie only counts as a lie if it registers as more of a lie than the control lie
so here's how you beat the test change your heart rate respiratory rate blood pressure and sweat
while answering the control questions send your control lies off the charts by comparison your
answers to the relevant questions whether you're telling the truth or not will seem true movies
like ocean's 11 have made famous techniques like pressing down on a thumbtack in your shoe to ramp
up your vitals during these control questions unfortunately these techniques are now so famous
test conductors will look for off-the-chart reactions to see if you're trying to fool the
test and sometimes they even make you take off your shoes so you have to be a bit more subtle
than this a better way is to think of scary or exciting thoughts when you recognize a control
question things like imagining you're walking across a tightrope a hundred stories in the air
and looking down at the ground or you can try to answer some complicated math problems in your head
like dividing 183 by four and since pain induces a similar physiological response as lying some will
recommend you bite down on your tongue or dig a fingernail into the tip of another finger but this
could be difficult to do unnoticed when you're sitting five feet away from your interrogator
then when you're answering relevant questions stay calm maintain your baseline
breathing pattern and let your mind be at ease thinking of waves washing ashore on the beach
even if you produce a slight response when asked the more intense relevant questions
you should have produced artificially stronger responses while answering the control questions
and thus be safe if you liked learning how you can pull one over on the feds be sure to watch
one of our other great videos here have a great day and remember there's always more to learn