Sold by the National Institute for Truth Verification, the CVSA (Computer Voice Stress Analyser) claims to be the “latest in truth verification instruments.” According to the site, “more than 1,700 local, state and federal agencies, including US military special operations and intelligence units utilize the CVSA® and CVSA®II.” Here is an interesting video on the system, demonstrating how it can fail, and questioning the credentials behind the inventor:

See also:

- How Lie Detectors Work

- How Police Interrogation Works

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