Voice Stress Analysis Technology Is Replacing Polygraphs
Nearly 1,900 U.S. law enforcement agencies have dropped the old polygraph in favor of the computer voice stress analyzer (CVSA) technology, according to the National Association of Computer Voice Stress Analysts (NACVSA), an organization representing more than 2,000 law enforcement, security, and military agencies worldwide.
CVSA works by measuring involuntary voice frequency changes that would indicate a high level of stress, as occurs when someone is being deceptive. Muscles in the voice box tighten or loosen, which changes the sound of the voice, and that is what the CVSA technology registers.
So far, police departments in Atlanta, New Orleans, Miami, and Nashville, Tenn., the California Highway Patrol, and many state and federal law enforcement agencies have made the switch to CVSA. Additionally, the NACVSA is doing a lot of work with law enforcement agencies across Europe, according to Kenneth Merchant, the organization's legislative director .
The technology, Merchant adds, has been gaining traction in the past few years, mainly due to its low cost, ease of operation, adaptability, and high accuracy rate
Additionally, the old polygraph has been discredited at the highest levels of government because of several high-profile cases where people, like NSA defector Edward Snowden and CIA traitor Aldrich Ames, beat the systems.
Interest in the CVSA by government agencies worldwide has increased dramatically due to research that found the accuracy rate of CVSA exceeds 95 percent. Polygraph, Merchant says, “is not nearly as close. Results can be inconclusive, which is not something that you have with CVSA.”