Protesting wrestlers say ready for narco test: What is it, how does it work

Sodium pentothal, or sodium thiopental, is a fast-acting, short-duration anaesthetic used in larger doses to sedate patients during surgery. It belongs to the barbiturate class of drugs that act on the central nervous system as depressants.

Because the drug is believed to weaken the subject’s resolve to lie, it is sometimes referred to as a “truth serum”, and is said to have been used by intelligence operatives during World War II.

However, narco tests must not be confused with polygraph tests, which, although having the same truth-decoding motive, work differently. A polygraph test is carried out on the assumption that physiological responses triggered when one is lying are different from what they otherwise would be. Rather than injecting drugs into the body, polygraph tests attach instruments like cardio-cuffs or sensitive electrodes to the suspect and measure variables such as blood pressure, pulse rate, respiration, change in sweat gland activity, blood flow, etc., while the suspect is being questioned.

Narco analysis tests were notably used in the 2002 Gujarat riots case, the Abdul Karim Telgi fake stamp paper scam, the Nithari killings case in 2007, and the 26/11 Mumbai terror attack case on captured terrorist Ajmal Kasab. However, it was in 2010 that the Supreme Court ruled on the legality and admissibility of narco tests.

What did the Supreme Court say?

In the 2010 Supreme Court ruling in “Selvi & Ors vs State of Karnataka & Anr” (2010), a Bench of the then Chief Justice of India KG Balakrishnan, and Justices RV Raveendran and JM Panchal held that no lie detector tests should be administered “except on the basis of consent of the accused”. Those who volunteer must have access to a lawyer and have the physical, emotional, and legal implications of the test explained to them by the police and the lawyer, the Bench added.

The court emphasised 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. Broadly, the guidelines say that such tests cannot be administered without the subject’s consent, which must be obtained before a Magistrate, and that the police cannot conduct them by themselves whenever they find it appropriate.

Taking into consideration the international norms on human rights, the right to a fair trial, and the right against self-incrimination under Article 20(3) of the Constitution, the court said, “We must recognise that a forcible intrusion into a person’s mental processes is also an affront to human dignity and liberty, often with grave and long-lasting consequences.

Relying on its 2010 ruling, a Supreme Court Bench of Justices BS Chauhan and SA Bobde in 2013 turned down the petition filed by the parents of the late Aarushi Talwar for producing narco-test reports conducted on the three persons initially accused in the case. Dismissing their plea, the court deemed their application a move to delay the trial proceedings at the final stage of the hearing.

In 2019, the CBI wanted to conduct narco-analysis tests on a former staffer of Punjab National Bank (PNB), who was in custody in the alleged Rs 7,000 crore fraud involving the absconding jewellers Nirav Modi and Mehul Choksi. However, the manager, Gokulnath Shetty, did not consent.

Last year, a Delhi court allowed the Delhi Police to conduct a narco test on Aaftab Poonawalla, who was accused of killing his live-in partner, Shraddha Walkar. Poonawalla consented to the test, telling the judge he was aware of the consequences.

What was the legal position before the SC ruling?

In 2006, the Madras High Court in Dinesh Dalmia v. State observed that since the accused did not come forward with the truth, the scientific tests resorted to by the investigating agency did not “amount to testimonial compulsion”. The court also stated, “When there is a hue and cry from the public and the human rights activists that the investigating sleuths adopt third degree methods to extract information from the accused, it is high time the investigating agency took recourse to scientific methods of investigation.”

Similarly, in the 2008 Delhi High Court ruling in “Sh. Shailender Sharma vs State & Another,” the court said that in light of the rising crimes against society, it is necessary to keep in mind the “need of a thorough and proper investigation as against individual rights while ensuring that constitutional rights are not infringed”. Adding that narco-analysis tests “do not suffer from any constitutional infirmity” and are a “step in aid of investigation”, the court allowed the administration of the test.

What is the evidentiary value of such tests?

While the results of narco-analysis tests are not considered “confessions” since those in a drugged-induced state cannot exercise their choice in answering questions put to them, the Supreme Court, through its 2010 ruling, clarified that “any information or material that is subsequently discovered with the help of voluntary administered test results can be admitted, in accordance with Section 27 of the Evidence Act, 1872.”

Thus, if an accused reveals the location of, say, a physical piece of evidence (something like a murder weapon) in the course of the narco test and the police later find that specific piece of evidence at that location, the statement of the accused will not be treated as evidence, but the physical evidence will be valid.