Quick answer
No. In Selvi v. State of Karnataka (2010), the Supreme Court held that no person can be forced to undergo narco-analysis, a polygraph (lie detector) test or a Brain Electrical Activation Profile (BEAP) test. Compelled testing violates the right against self-incrimination under Article 20(3) and personal liberty, including mental privacy, under Article 21. The tests may be done only with free consent recorded before a Judicial Magistrate, and even then the test results themselves are not admissible as evidence.
The case
Smt. Selvi v. State of Karnataka, (2010) 7 SCC 263, AIR 2010 SC 1974, Supreme Court of India, 5 May 2010, three judges (K.G. Balakrishnan, C.J.I., R.V. Raveendran and J.M. Panchal, JJ.; opinion by Balakrishnan, C.J.I.). Held that the involuntary administration of narco-analysis, polygraph and BEAP tests amounts to testimonial compulsion (being forced to give evidence from one's own knowledge) and is barred by Article 20(3). It also unjustifiably intrudes on mental privacy and amounts to cruel, inhuman or degrading treatment under Article 21.
Why these tests are different
Article 20(3) says no person accused of an offence shall be compelled to be a witness against himself. An eleven-judge bench in State of Bombay v. Kathi Kalu Oghad (1961) held that taking fingerprints or specimen handwriting does not violate Article 20(3). Building on it, Selvi treated bodily samples such as blood, hair or DNA as physical evidence, not "testimony", so they may be taken without consent under the procedure law provides. The Court held that narco-analysis, polygraph and BEAP results are different: they convey what a person knows, even if the response is physiological rather than spoken. That makes them personal testimony, which Article 20(3) protects.
Essential points
- No forced testing of anyone: the bar covers accused persons, suspects, witnesses and even victims, in criminal investigations or otherwise.
- Not "medical examination": the words "such other tests" in the Explanation to Sections 53, 53A and 54 of the Code of Criminal Procedure, 1973 (old law) cannot be stretched to include these techniques. The same words now appear in the Explanation to Section 51 B.N.S.S., which applies to Sections 51, 52 and 53 B.N.S.S.
- Voluntary tests allowed only with safeguards: the Court adopted the NHRC's 2000 guidelines for polygraph tests and applied similar safeguards to the other two tests. These include free consent, access to a lawyer, consent recorded before a Judicial Magistrate, testing by an independent agency (such as a hospital) in the lawyer's presence, and a full record of the process.
- Results are not evidence: even voluntary test results cannot be admitted, because the subject has no conscious control over the responses. Only a fact later discovered from information obtained in a voluntary test can be proved, under Section 27 of the Indian Evidence Act, 1872 (old law).
Physical evidence and mental testimony compared
| Point | Physical evidence (fingerprints, blood, DNA) | Narco-analysis, polygraph, BEAP |
|---|---|---|
| Nature | Material evidence about the body | Personal testimony from the mind |
| Article 20(3) | Not attracted | Attracted if compelled |
| Can it be taken without consent? | Yes, under the procedure law provides | No |
| Use in trial | Admissible, subject to proof | Results inadmissible; only facts discovered may be proved |
Police suspect Farhan of a burglary and ask a court to order a narco-analysis test because he refuses to talk. After Selvi, the court cannot order it without his consent. If Farhan agrees, his consent must be recorded before a Judicial Magistrate with his lawyer present. If the test leads police to stolen jewellery hidden in a shed, the recovery and the part of the information that led to it may be proved, but the test report itself cannot be used as evidence of guilt.
Current law note
The Code of Criminal Procedure, 1973 and the Indian Evidence Act, 1872 have been replaced. Section 51 B.N.S.S. now governs medical examination of an arrested person at the request of the police, and the discovery rule of old Section 27 is now the proviso to Section 23(2) B.S.A. Selvi's constitutional holding under Articles 20(3) and 21 applies unchanged. The Court's link between Article 21 and mental privacy also fits the later recognition of privacy as a fundamental right in Justice K.S. Puttaswamy v. Union of India (2017).
Exam point
Selvi (2010): compelled narco-analysis, polygraph and BEAP tests are testimonial compulsion barred by Article 20(3) and violate mental privacy under Article 21; voluntary tests need consent before a Judicial Magistrate, and their results are never admissible, only discovered facts are.
