Evidence Law
Selvi v. State of Karnataka
(2010) 7 SCC 263
- Citation
- (2010) 7 SCC 263
- Court
- Supreme Court of India
- Date
- 5 May 2010
- Bench
- K.G. Balakrishnan CJI, R.V. Raveendran and J.M. Panchal JJ.
Facts
- A group of criminal appeals challenged court orders allowing investigating agencies to conduct:
- narcoanalysis;
- polygraph examinations;
- Brain Electrical Activation Profile tests, commonly called brain mapping.
- The proposed subjects included:
- accused persons;
- suspects;
- witnesses.
- In narcoanalysis:
- drugs such as sodium pentothal are administered;
- inhibitions are reduced;
- the subject is encouraged to speak while in an altered state.
- Polygraph examinations record physiological responses while questions are asked.
- BEAP tests measure electrical brain responses to determine familiarity with particular information.
- Investigating authorities argued that these techniques:
- would assist difficult investigations;
- were less harmful than physical coercion;
- could produce useful investigative leads;
- need not themselves be used as trial evidence.
- The subjects argued that involuntary testing violated:
- Article 20(3);
- personal liberty under Article 21;
- mental privacy;
- bodily integrity;
- the right to a fair investigation and trial.
- Doubts were also raised about the scientific reliability of the techniques.
Issue
- Whether involuntary administration of the tests amounts to testimonial compulsion.
- Whether Article 20(3) applies during investigation and to suspects as well as formally charged accused.
- Whether such testing violates Article 21, privacy and bodily integrity.
- Whether test results or discoveries made from them are admissible.
Rule
- Article 20(3) protects an accused against compelled testimonial self-incrimination.
- The protection applies at the investigation stage and is not confined to testimony in court.
- Testimonial evidence includes involuntary methods which extract or reveal the subject’s personal knowledge.
- It is not limited to ordinary spoken answers.
- Narcoanalysis, polygraph and BEAP results involve the use of the subject’s mental processes to draw conclusions about relevant facts.
- They are different from physical evidence such as:
- fingerprints;
- blood samples;
- handwriting specimens.
- Involuntary administration also violates Article 21 by interfering with:
- mental privacy;
- bodily integrity;
- human dignity;
- protection against cruel, inhuman or degrading treatment;
- trial fairness.
- Voluntary testing may be conducted only with informed consent and prescribed safeguards.
- Even where a test is voluntary, the actual test results are not automatically substantive evidence.
- A material fact independently discovered as a result may be admissible under the discovery rule, subject to voluntariness and other evidentiary requirements.
Application
- The Court rejected the argument that only verbal answers are testimonial.
- A polygraph response or brain-activation pattern may communicate familiarity, recognition or deception derived from the subject’s mind.
- Such responses disclose personal knowledge and therefore possess a testimonial character.
- Narcoanalysis was even more directly testimonial because the drug induces verbal revelations while reducing conscious control.
- The Court emphasised that lack of conscious control does not make the revelation voluntary.
- It instead increases the compulsion.
- These techniques also produce unreliable results:
- narcoanalysis may generate fantasies, suggestions or false information;
- polygraph readings can be affected by anxiety and physiological differences;
- BEAP may show familiarity without proving participation in a crime.
- Using such uncertain material may prejudice:
- the presumption of innocence;
- the right to challenge prosecution evidence;
- the fairness of the trial.
- The State’s duty to investigate efficiently could not justify forcing entry into a person’s mental processes.
- Investigators must ordinarily build their case through independent efforts.
- The Court distinguished Kathi Kalu Oghad.
- Fingerprints and handwriting are external physical characteristics.
- The impugned tests attempted to extract the subject’s personal knowledge and mental responses.
- Consent had to be genuine and informed.
- Judicial authorisation alone could not replace the individual’s consent.
- Where voluntary testing is permitted, safeguards laid down by the National Human Rights Commission must be followed.
Conclusion
- The Supreme Court held that involuntary narcoanalysis, polygraph and BEAP testing is unconstitutional.
- It violates:
- Article 20(3);
- substantive due process under Article 21;
- mental privacy;
- bodily integrity.
- No individual, whether accused, suspect or witness, may be forcibly subjected to these techniques.
- Voluntary tests require informed consent and procedural safeguards.
- The test results themselves do not automatically become admissible substantive evidence.
- Independently discovered material may be considered only under ordinary evidence rules and where voluntariness is established.