In a major blow to investigating agencies, the Supreme Court on Wednesday declared as “illegal” use of narcoanalysis, brainmapping and polygraph tests on suspects.
Narco, polygraph or brainmapping tests cannot be conducted on any person, whether an accused or a suspect, without their consent, the SC’s judgement said.
“We are of the considered opinion that no individual can be forced and subjected to such techniques involuntarily, and by doing so it amounts to unwarranted intrusion of personal liberty,” a bench headed by Chief Justice K G Balakrishnan said.
The apex court said that involuntarily subjecting an accused, a suspect or a witness to such techniques violates Article 20 (3) of the Constitution, which prohibits self-incrimination.
Forcing an individual to such methods of investigation violates the scheme of legal process, it said, adding that even if such tests are taken voluntarily then also results cannot be used as evidence unless corroborated by other evidence.
However, the bench also comprising Justices R V Raveendran and Dalveer Bhandari said if anything obtained by the investigators from such techniques in which a person had volunteered, the agencies can use them for further probe.