Polygraph Test

Aug. 26, 2024

Recently, the Central Bureau of Investigation (CBI) conducted a polygraph test on the main suspect in the R G Kar Medical College and Hospital case.

About Polygraph test:

  • The polygraph test operates on the premise that physiological responses triggered when a person is lying differ from their responses when they are being truthful.
  • During the test, instruments such as cardio-cuffs or sensitive electrodes are attached to the suspect to measure variables such as blood pressure, pulse rate, respiration, sweat gland activity, and blood flow as questions are posed.
  • Evaluation: Each response is given a numerical value to determine whether the individual is telling the truth, being deceptive, or uncertain.

Supreme Court Judgements:

  • According to the judgment of the Supreme Court in Selvi & Ors vs State of Karnataka & Anr (2010):
    • Polygraph tests can only be administered with the accused’s consent.
    • Consent must be informed, with the accused having access to legal counsel and a thorough explanation of the test’s physical, emotional, and legal implications.
    • The National Human Rights Commission’s Guidelines for polygraph tests, issued in 2000, must be strictly adhered to.
    • The accused’s consent should be documented before a Judicial Magistrate.
    • Any evidence or information obtained through a voluntarily consented polygraph test can be admitted in court.