Criminal polygraph examinations, also known as “lie detector tests”
are considered useful investigative tools to support criminal investigations.
To local police officers and detectives, polygraphs help them eliminate
or include criminal suspects in criminal investigations.
For example, if a suspect were to pass a polygraph with “flying colors,”
it can help the police rule the suspect out. Conversely, if a suspect
fails miserably, it can indicate that he or she may have something to hide.
If a suspect performs poorly on a polygraph, the police can use the results
to seek additional information and a confession from the now increasingly
suspicious individual. However, polygraph examinations are not foolproof
and they don’t perform miracles. Just because someone fails a polygraph,
it doesn’t mean the case is a slam-dunk for the prosecution –
a lie detector test is no substitution for a full-blown criminal investigation.
How the Polygraph Test Works
According to the
Austin Police Department, “the polygraph test uses three types of physiological components
that monitor physiological changes; respiratory rate, blood pressure/heart
rate and galvanic skin responses.”
“In the state of Texas, polygraph results are not admissible into
a court of law; however, if a legally obtained confession is obtained
during the course of a post-test interview, the Examiner in some cases
will be subpoenaed to testify as to the details of that confession under
oath,” says the Austin Police Department.
Should I Take a Lie Detector Test?
As we mentioned above, polygraph examinations are inadmissible in court.
If you’re being asked to take a lie detector test, remember, you
don’t have to prove your innocence. You are innocent until proven
guilty and the police are not on your side.
The police utilize various tools and tactics to get confessions out of
suspects, including polygraphs. So, why say “Yes,” when you
don’t have to? Our advice is to
contact a Plano criminal defense attorney at our firm immediately and STOP talking to the police.