The Polygraph, being only one of the Methods of Lie Detecting, has become the descriptive word most people use when talking about Truth Verification and Lie Detecting. It is often the preferred Method purely due to its’ history.
It is an instrument that simultaneously measures thoracic and abdominal breathing patterns, relative changes in blood volume and the resistance of electricity in sweating. During an examination, the examinee is connected to the instrument and then monitored to see how his or her body reacts measured against those parameters when being asked questions. Convoluted rubber tubes that are placed over the examinee’s chest and abdominal area record respiratory activity. Two small metal plates attached to the fingers record sweat gland activity, and a blood pressure cuff or similar device records cardiovascular activity. This means that it is an instrument that is used to measure and record certain responses coming from the body when the examinee is asked questions to indicate whether or not he or she is telling the truth.
In a Specific examination the test is conducted at the hand of specific facts provided to the examiner concerning a specific incident. A pre-test interview with the person requesting the test is crucial to determine exactly what the main objective of the test should be, and what should be established by means of the test.
PRE-EMPLOYMENT POLYGRAPH TESTS
In this instance the examination is utilized mainly to determine the subject’s honesty with regard to his employment application and possible deviant behavior at previous places of employment. This kind of test is highly recommended for new applications in key positions in any business.
PERIODIC POLYGRAPH TESTS (SCREENINGS)
Polygraph tests can also be utilized to determine the general honesty of existing employees from time to time, in an effort to separate the trustworthy employees from the deceptive ones.
Frequently Asked Question:
Q. When is Polygraph testing preferable over Voice Stress Analysis?
A: Polygraph testing is mostly used in cases of serious crime.