AUTHOR: VAISHNAVI TRIPATHI, ARYA KANYA DEGREE COLLEGE, UNIVERSITY OF ALLAHABAD
To the Point
The evolution of criminal investigation in India has seen increasing reliance on scientific techniques like narco-analysis, brain mapping, and polygraph tests. These methods, while potentially useful, raise complex questions about constitutional rights, particularly the right against self-incrimination under Article 20(3) and the right to privacy under Article 21. This article analyses their legal standing, scientific reliability, and international treatment, culminating in a clear verdict on their role in modern Indian jurisprudence.
Use of Legal Jargon
Narco-Analysis: A psycho-chemical technique using sedatives (e.g., sodium pentothal) to extract suppressed memories during a semi-conscious state.
Brain Mapping: A neuro-scientific technique that detects brainwave responses (like P300) when the subject is shown crime-related stimuli.
Polygraph: It’s commonly known as a lie detector, measures a person’s physical responses such as heart rate, blood pressure, and breathing patterns—to determine if they might be lying.
Voluntariness: A principle in criminal law requiring that statements or actions by the accused be free from coercion.
Self-incrimination: The act of implicating oneself in a crime, particularly under duress or compulsion, prohibited under Article 20(3).
The Proof
Recent years have witnessed a surge in the use of these techniques in criminal investigations involving complex, high-profile, and media-sensitive cases. Law enforcement argues that in the absence of direct evidence, such techniques are indispensable. However, constitutional experts warn that these tests, if conducted involuntarily, violate the essence of due process and dignity guaranteed under the Constitution.
In 2023 and 2024, cases like the NEET paper leak, Vivek Sagar custodial death, and the Mumbai triple homicide revived demands for wider acceptance of forensic technologies. Police departments across India continued to propose such tests, but courts remained firm on the necessity of voluntary consent and judicial oversight.
Abstract
This article examines the legality, constitutionality, and scientific validity of brain mapping and narco-analysis in India. It analyses whether these tools, often presented as objective and cutting-edge, actually withstand the test of constitutional scrutiny. Using a doctrinal approach, it interprets case laws, legal provisions, and forensic critiques to conclude that involuntary forensic interrogation methods are unconstitutional, ethically suspect, and scientifically dubious. It proposes legislative reforms, procedural safeguards, and stricter ethical standards for their controlled use, if at all.
Case Laws
1. Selvi v. State of Karnataka, (2010)
7 SCC 263
Most definitive judgment. The Supreme Court ruled that involuntary administration of these techniques is unconstitutional under:
Article 20(3) – Right against self-incrimination
Article 21 – Right to personal liberty and mental privacy.
The court noted:
“The forcible interference with a person’s mental processes is a grave affront to human dignity and autonomy.”
Selvi set down that:
These tests can only be conducted with free, informed, and written consent.
Even when voluntarily taken, the results cannot be treated as confessions but may be used only as corroborative evidence.
2. Rojo George v. Deputy Superintendent of Police, (2017)
SCC Ker 389
Reinforced Selvi by holding that results obtained without valid consent are inadmissible, regardless of the gravity of the crime.
3. Nithari Killings Case (2006)
Brain mapping and narco-analysis were used on the accused, Surinder Koli and Moninder Singh. While these yielded details, none of the statements were treated as admissible due to lack of voluntariness.
4. Sheena Bora Murder Case (2015–2023)
CBI sought narco-analysis on Indrani Mukerjea, but the application was withdrawn due to her refusal to consent. The court upheld her right to refuse.
Statutory Framework & Policy Gaps
Currently, there is no legislation in India that directly governs the use of narco-analysis or brain fingerprinting. They operate through:
Judicial guidelines (Selvi)
Code of Criminal Procedure (CrPC) – general provisions on admissibility
Medical Council of India (now NMC) – ethical codes for doctors
Legal Gaps:
No uniform protocol across states
Absence of a data protection law to safeguard mental data
No provision for independent legal counsel during the test
Lack of post-test psychological care for subjects
Ethical & Scientific Concerns
1. False Positives: Drugs used in narco-analysis can impair memory and judgment.
2. Mental Trauma: Brain mapping can trigger psychological distress.
3. Voluntariness in Doubt: Consent in police custody is inherently suspect.
4. Scientific Validity: Brain fingerprinting is not universally accepted; studies on accuracy are inconsistent.
5. Violation of Dignity: Treating a person as a “subject” rather than a rights-bearing ind
individual undermines constitutional values.
Conclusion
Brain fingerprinting, narco-analysis, and polygraph tests promise investigative breakthroughs, but their use must never compromise constitutional liberties. The Supreme Court in Selvi rightly drew a red line: no technique that intrudes into the mental privacy of a person without informed, voluntary consent can be permitted.
India needs a dedicated legislation governing the scope, methodology, and admissibility of forensic interrogation techniques. Until such a law is enacted, courts must continue to act as constitutional sentinels, ensuring that the quest for truth does not override the foundational rights of liberty, dignity, and fairness.
FAQs
Q1: Are brain mapping and narco-analysis legal in India?
Ans: They are legal only with the subject’s voluntary and informed consent. Involuntary tests are unconstitutional under Selvi v. State of Karnataka.
Q2: What constitutional rights are violated by forced tests?
Ans: Article 20(3): Protection against self-incrimination,
Article 21: Right to privacy and dignity.
Q3: Can we really trust these tests to tell the truth?
Ans: Not completely. Experts still debate how reliable they are. Narco-analysis can sometimes bring out false or imagined memories, and brain mapping doesn’t have a uniform method of testing, which makes the results less dependable.
Q4:Do other countries use such tests?
Ans: Most democratic nations like the USA, UK, and Canada prohibit these tests due to ethical and legal concerns.
Q5: Can such tests be used as evidence in court?
Ans: Only if voluntarily administered and often only as corroborative, not primary, evidence.
