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About Polygraph

What you really need to know

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WHAT IS A POLYGRAPH?

A polygraph used for the purpose of lie detection is an instrument that monitors and records various manifestations of the Sympathetic and Parasympathetic Nervous Systems while a series of carefully designed questions is asked of the person who is attached to the instrument. [read more]

POLYGRAPH ACCURACY

In a specific issue test, using a validated technique, average accuracy will exceed 90%. The accuracy of a polygraph depends heavily on the following elements. [read more]

WHY IS IT IMPORTANT TO USE A VALIDATED TESTING TECHNIQUE?

A validated testing technique is one that has been validated by the American Polygraph Association, though research, to achieve a minimum level of accuracy (90% for specific issue tests, 80% for multiple issue tests). Other techniques are less accurate and are not supported by scientific research. Click HERE to see the Validated Techniques.

THERE IS NO SUCH THING AS A LIE DETECTOR

If polygraphs don't detect lies, then what do they detect? [read more]

WHAT IT'S LIKE TO TAKE A POLYGRAPH

Click HERE to experience what it's like to undergo a typical polygraph exam.

RULES FOR DESIGNING POLYGRAPH QUESTIONS

There are quite a few rules for designing proper polygraph questions. Your examiner will work with you to develop the best questions for your situation, but here are some of the basic rules for question design. [read more]

CAN A MODERN POLYGRAPH BE FOOLED?

The polygraph works by recording changes in a person's Sympathetic Nervous System, part of the Autonomic Nervous System, which operates independently of conscious thought.  [read more]

HISTORY OF POLYGRAPH

Since a polygraph is actually several instruments combined into one, each component was developed independently of the others. These components were finally combined in 1938. [read more]