Lie Detection and Polygraphs

Lie Detection Test

 

At Uphando we use two types of lie detection tests namely, the polygraph test or the voice-stress analysis. Many will favour the voice-stress analysis as it enables the investigator to question the individual more freely whereas the polygraph test only allows a certain amount of questions to be directed at the individual.

Polygraph Test

The instrument typically used to conduct polygraph tests consists of a physiological recorder that assesses three indicators of autonomic arousal:

– Heart rate/blood pressure

– Respiration, and

– Skin conductivity.

Most examiners today use computerized recording systems.

Voice Stress Analysis

Voice stress analysis (VSA) and Computer Voice Stress Analysis (CVSA) are collectively a pseudoscientific technology that aims to infer deception from stress measured in the voice.