Computer Voice Stress Analyzer (CVSA)

Computer Voice Stress Analyzer - Hannibal Police Department***Unlike the computer polygraph, the CVSA® requires no wires be attached to the subject being tested. The CVSA® uses only a microphone plugged into the computer to analyze the subject's responses. As the subject speaks, the computer displays each voice pattern, numbers it and saves each chart to file. Unlike the polygraph, drugs do not affect the results of the exam and there are no known counter-measures that will cause the ubiquitous "inconclusive" results associated with the polygraph.

The CVSA® is effective in all investigative situations such as homicide, sex crimes, robbery, white collar crimes, and internal affairs investigations, as well as pre-employment examinations for background investigators. Embraced by the Department of Corrections, the system has also proven itself a very reliable investigative tool for verifying statements of witnesses, denials of suspects, and for determining the validity of allegations made against police officers.

Micro tremors are tiny frequency modulations in the human voice. When a test subject is lying, the automatic, or involuntary nervous system, causes an inaudible increase in the Micro tremor's frequency. The CVSA® detects, measures, and displays changes in the voice frequency.

A state-of-the-art computer processes these voice frequencies and graphically displays a picture of the voice patterns. The CVSA® is not restricted to "yes" and "no" answers and is able to analyze accurately, tape recordings of unstructured conversations.

Introduced into the law enforcement community in 1988, the original analog CVSA® became an instant success at every agency that purchased it, solving crimes that, in some cases, had languished for years (cold cases). In other cases, individuals that were either untestable or had been called "inconclusive" on the old polygraph agreed to take a CVSA® exam and subsequently confessed to their crimes. With such results, it wasn't long before word-of-mouth spread the CVSA®'s reputation like wild-fire in the law enforcement community. Today's CVSA® has been digitized and incorporated into a powerful multi-functional notebook computer. The latest version of the CVSA® enjoys the reputation of being the most effective investigative tool to be introduced into the law enforcement community within the past three decades.

When used in conjunction with the National Institute for Truth Verification's (NITV®) interviewing and interrogation techniques, including its widely acclaimed Defense Barrier Removal (DBR®) technique to obtain confessions, the results are swift and dramatic. "Cold" cases are solved by analyzing old interview tapes. The CVSA® gets to the truth and accurately identifies deception, or validates statements in the shortest possible time (average exam time is 40 minutes.). ***

*** (Information from the CVSA Website located at