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Polygraph F.A.Q.

What is a Polygraph?

A polygraph is a scientific instrument used to detect deception.

The term "polygraph" literally means "many writings." The name refers to the manner in which selected physiological activities are simultaneously recorded. Polygraph examiners may use conventional instruments, sometimes referred to as analog instruments, or computerized polygraph instruments. Most polygraph examiners in the United States now use computerized polygraph instruments.

According to the dictionary the polygraph is a measuring device, which makes a permanent recording of various physiological changes taking place within the body of the test subject as a result of certain psychological stimuli. These stimuli are brought about by asking questions, structured and phrased in a specific way, and by maintaining a certain environmental and emotional climate during the examination.

Who is a Polygraph Examiner?

A person who has graduated from an American Polygraph Association approved basic polygraph examiner course of instruction and is properly licensed as required by law.

How does a Polygraph work?

The polygraph records physiological responses of an individual attached to a polygraph instrument.

What does the Polygraph record?

A polygraph records, breathing, heart rate, blood pressure, blood volume, and galvanic skin resistance.

Does a polygraph detect lies?

No, a polygraph records physiological responses to a series of questions presented to an individual by a qualified polygraph examiner using a validated testing format. The examiner is then able to decipher the chart polygrams and render a diagnostic opinion as to the veracity of the subject being tested.

Can an employer use a polygraph to test an employee suspected of causing an economic loss?

Yes, if the employer has reasonable suspicion. The employer must be able to articulate the reasonable suspicion, and reduce it to writing, access alone does not constitute reasonable suspicion. Additional information can be found in the Employee Polygraph Protection Act.

How accurate is a polygraph?

The American Polygraph Association says the polygraph is 85% to 95% accurate, there are studies on record that suggest polygraph is even more accurate.

How many questions may be asked? 

Question numbers are determined by the format being utilized by the examiner.

Will I know what questions are on the test?

Yes, all questions are reviewed with the examinee prior to any polygraph testing.

Can I be forced to take a polygraph exam?

No, polygraph exams are always voluntary.

How long does a polygraph exam take? 

Examinations require a minimum of ninety minutes, but often take longer.

Should I stop taking my medication before the test?