You have probably heard many stones about lie detectors. The truth is that a lie detector has never been invented!

No instrument or machine detects lies. No machine, instrument, computer, or software program today is capable of distinguishing truth from deception.

Back in the 1930’s, the early days of the polygraph, the news media coined the phrase lie detector. The polygraph examiners liked it and exploited it. They liked to call that crude instrument a lie detector and many still do. But, the polygraph has never detected a single lie.

Since 1927, there has not been a significant change in the polygraph. There have been improvements such as changing from mechanical instrumentation to electronic, and recently from electronic to digital. Many mechanical devices are still in use today. The polygraph is an instrument that detects, measures, and graphically displays certain physiological reactions to psychological stimuli, those reactions are from stress.

What is STRESS? Stress is any action or situation that places special physical or psychological demands upon a person, anything that upsets his individual equilibrium.

Stress, induced by fear, guilt, anxiety or conflict facilitates detection of attempted deception.

Detection of attempted deception, as distinguished from mere identification of stress, is a decision based upon a human analytical process which equates attempted deception to displayed stress by the control of variables. This is normally accomplished by specific test construction or test protocol together with certain interrogation techniques.

That is what lie detection is, regardless of the instrument utilized. So it is the trained examiner who attempts to determine what is truthful and what is not truthful.

No instrument, including the polygraph, the CVSA, LVA, the LanternPro or the PSE detects lies.

The polygraph procedure itself poses a number of problems, which have never been overcome. The attaching of sensors, a sometimes painful blood pressure cuff and bellows across the chest and stomach, together with a severe testing atmosphere, create a false psychological set which frequently is greater than that which the examiner VSA and Polygraph Controversy is attempting to evaluate, hence some inconclusive or erroneous decisions by the examiner.

Expert medical testimony has revealed there are certain persons who should not undergo a forensic polygraph examination. Those are persons who have: 

excessive fatigue, prolonged interrogation, physical abuse, sub-shock or adrenal exhaustion, excessively high or low blood pressure, heart disease, respiratory disorders, psychoses or evidence of drugs, especially tranquilizers or stimulants.

For many years polygraphers inquired into sexual activities or other personal matter in an effort to create a stimulus above the false psychological set. Some polygraphers still do. Many consider the polygraph procedure to be abusive or degrading or providing insufficient accuracy of interpretation.

What is VOICE STRESS ANALYSIS? Introduced in 1970 in an analog mode and constantly improved and upgraded to its current digital autographic software driven notebook computer such as the TruthTec LanternPro VSA requires no attached sensors and no severe testing atmosphere or abusive questioning.
Real time examinations or tape recordings are made of the conversation or tests and then computer processed utilizing up to 96 displays of each utterance for display on the notebook screen or printed for future analysis. This permits extraordinary in-depth analysis.

Because VSA procedure measures both the autonomic and the central nervous systems, it is capable of displaying both absolute stress of any utterance, but also displays relative stress of utterance comparisons. This permits the analysis of narrative or discussions in addition to one word answers such as yes and no.

Polygraph instruments are limited to yes and no answers only and are limited to relative stress analysis.

Nervousness and drugs have little effect on VSA results. Without the attached sensors, there is relatively little falsely induced stress with VSA. Therefore, there are no Inconclusive or erroneous evaluations by a well-trained VSA examiner.

It takes expert training and a great deal of experience with continuing study to make a competent VSA examiner.

The truth cannot be altered, only revealed.
VSA and Polygraph Controversy