- The Central Bureau of Investigation (CBI) completed polygraph tests on seven people in connection with the rape and murder of a resident doctor at the R.G. Kar Medical College and Hospital in Kolkata.
- A polygraph test–popularly known as a lie detector test–is a machine that measures a person’s physiological responses when they respond to questions.
- According to the American Psychological Association (APA), polygraph tests measure a person’s “heart rate/blood pressure, respiration, and skin conductivity.”
- A numerical value is then assigned to each response to determine whether the person is truthful, deceptive, or uncertain.
- The test’s origins trace back to the 19th century when Italian criminologist Cesare Lombroso used a machine to measure changes in blood pressure during interrogations.
- On the contrary, the Narco test also known as a narco-analysis test involves injecting the subject with sodium pentothal, also known as “truth serum”, to induce a hypnotic or sedated state. The theory is that in this state, the subject’s imagination is neutralized and they will speak the truth.
- Despite their use in investigations, polygraph tests, like Narco tests, have not been scientifically proven to have a 100% success rate and remain controversial in the medical field.
| Legal Status of Polygraph Test in India • Polygraph, narco-analysis, and brain mapping tests without the accused’s consent violate Article 20(3) of the Indian Constitution, which protects against self-incrimination. • Courts in India often criticised these tests, violating the right to life and privacy under Article 21. • In Selvi v. State of Karnataka & Anr (2010), the Supreme Court ruled that involuntary narco or polygraph tests violate the right against self-incrimination and intrude on mental privacy. • Any material or information discovered with the help of such a voluntarily taken test can be admitted as evidence. • SC also said that the ‘Guidelines for the Administration of Polygraph Test on an Accused’ published by the National Human Rights Commission in 2000, must be strictly followed. |
Dig Deeper: Read about NHRC guidelines for conducting a Polygraph Test.
