Baba’s Explainer – Narco Test

  • IASbaba
  • November 21, 2022
  • 0
Governance, Science and Technology
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  • GS-3: Science and Technology
  • GS-2: Governance & Human Rights

Context: A court in Saket, New Delhi, has allowed Delhi Police to conduct a narco test on Aaftab Poonawalla, the 28-year-old man accused of killing his 27-year-old live-in partner Shraddha Walkar in May 2022.

  • Poonawalla allegedly chopped up Walkar’s body in many pieces, and disposed of them in a wooded area in South Delhi over several weeks.
  • After police moved court seeking permission for the test, Poonawalla consented, telling the judge he was aware of the consequences.
What is a narco test?
  • In a ‘narco’ or narcoanalysis test, a drug called sodium pentothal is injected into the body of the accused, which transports them to a hypnotic or sedated state, in which their imagination is neutralised.
  • In this hypnotic state, the accused is understood as being incapable of lying, and is expected to divulge information that is true.
  • Sodium pentothal or sodium thiopental is a fast-acting, short duration anaesthetic, which is 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.
Is this the same as a polygraph test?
  • A polygraph test is based on the assumption that physiological responses that are triggered when a person is lying are different from what they would be otherwise.
  • A polygraph test does not involve injecting drugs into the body; rather instruments like cardio-cuffs or sensitive electrodes are attached to the suspect, and variables such as blood pressure, pulse rate, respiration, change in sweat gland activity, blood flow, etc., are measured as questions are put to them.
  • A numerical value is assigned to each response to conclude whether the person is telling the truth, is deceiving, or is uncertain.
  • A test such as this is said to have been first done in the 19th century by the Italian criminologist Cesare Lombroso, who used a machine to measure changes in the blood pressure of criminal suspects during interrogation.
But why should tests such as these be done?
  • In recent decades, investigating agencies have sought to employ these tests in investigation, which are sometimes seen as being a “softer alternative” to torture or “third degree” to extract the truth from suspects.
  • However, neither method has been proven scientifically to have a 100% success rate, and remain contentious in the medical field as well.
What exactly is the BEOSP test?
  • Brain Electrical Oscillation Signature Profiling (BEOSP) also known as brain fingerprinting is a neuro psychological method of interrogation in which the accused’s participation in the crime is investigated by studying their brain’s response.
  • The BEOSP test is carried out via a process known as electroencephalogram, conducted to study the electrical behaviour of the human brain.
  • Under this test, the consent of the accused is first taken and they are then made to wear caps with dozens of electrodes attached to them.
  • The accused are then shown visuals or played audio clips related to the crime to check if there is any triggering of neurons in their brains which then generate brainwaves. 
  • The test results are then studied to determine the participation of the accused in a crime
  • To be fair to the accused, forensic experts also prepare probes on the basis of their alibis and then present two hypothesis in front of them to invoke their brain’s reaction.
  • The tests are based on the phenomenons of ‘knowledge’ and ‘experience’. A person’s brain might have knowledge of the crime committed and the alibi they have come up with. But it is the ‘experience’ of having participated in the crime that determines their guilt.
What differentiates a BEOSP test from a polygraph or a lie detector?
  • The BEOSP procedure does not involve a question answer session with the accused and is rather a neuro psychological study of their brain.
  • In a polygraph test, the accused person’s physiological indicators are taken into account which include blood pressure, pulse rate, respiration and skin conductivity.
  • However, experts say that while a person might be able to control their pulse rate and BP even in times of distress, a BEOSP test offers a much more credible result.
Are there no restrictions on putting accused through these tests?
  • There is, indeed. In ‘Selvi & Ors vs State of Karnataka & Anr’ (2010), a Supreme Court ruled that no lie detector tests should be administered “except on the basis of consent of the accused”.
  • The subject’s consent should be recorded before a judicial magistrate.
  • Those who volunteer must have access to a lawyer, and have the physical, emotional, and legal implications of the test explained to them by police and the lawyer, SC said.
  • Also, the guidelines by the National Human Rights Commission in 2000, must be strictly followed.
Can the results of these tests be considered as “confessions”?
  • No, because those in a drugged-induced state cannot exercise a choice in answering questions that are put to them.
  • The Bench took into consideration international norms on human rights, the right to a fair trial, and the right against self-incrimination under Article 20(3) of the Constitution.
  • However, any information or material subsequently discovered with the help of such a voluntarily-taken test can be admitted as evidence, the Supreme Court said.
  • Thus, if an accused such as, say, Poonawalla, reveals the location of, say, a physical piece of evidence (which is often something like a murder weapon) in the course of the test, and 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 treated as such.
In which recent criminal investigations have these tests been sought to be used?
  • There have been several.
  • The CBI had sought to give these tests to the driver and helper of the truck that hit the vehicle carrying the Unnao rape victim in Uttar Pradesh in July 2019.
  • In May 2017, Indrani Mukerjea, who is facing trial for allegedly murdering her daughter Sheena Bora in 2012, had offered to undergo the lie detector test. The CBI refused, saying they already had sufficient evidence against her.
  • Dr Rajesh Talwar and Dr Nupur Talwar, who were accused of killing their daughter Aarushi and help Hemraj in Noida in 2008, were given polygraph tests. A video of the narco test on their compounder, Krishna, was leaked to the media.
  • In August 2019, the CBI wanted to conduct polygraph and narcoanalysis 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. The manager, Gokulnath Shetty, declined consent.

Main Practice Question: What are the latest technologies used in interrogations by Police? What legal restrictions are in place to prevent the misuse of such technologies?

Note: Write answer his question in the comment section.

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