Evaluation of Voice Stress Analysis Technology

The Air Force Research Laboratory (AFRL) has been tasked by the National Institute of Justice to investigate voice stress analysis (VSA) technology and evaluate its effectiveness for both military and law enforcement applications. This technology has been marketed as commercially available in computer-based form, and marketed as being capable of measuring stress and in some systems deception. This technology is reported as being easier to use, less invasive, and less constrained in their operation than standard polygraph technology. This study has found that VSA technology can identify stress better than chance with performance approaching that of current polygraph systems. However, it is not a technology that is mature enough to be used in a court of law. We also found that experience and training improves the accuracy over less trained individuals. Lastly, we explored how this technology may become an effective interrogation tool, when combined with polygraph technology.