- Entries A-Z
An instrument, also called a polygraph, used to record physiological reactions during questioning. Involuntary physical reactions (e.g., blood pressure increases, pulse, perspiration, and respiration) are measured to indicate whether the answers are truthful. Most legal jurisdictions do not allow the use of polygraph results in court testimony because their accuracy is questionable. However, it is a useful tool in law enforcement investigations and in some treatment settings.