The full text of the landmark judgment of the Supreme Court in the case of Selvi v State of Karnataka is available here. I have not read the judgment yet, but media reports suggest that the Court has held that involuntary subjection of a person to narco-analysis, polygraph test and brain-mapping violates Article 20(3) of the Constitution, which provides that ‘No person accused of any offence shall be compelled to be a witness against himself.’ (the ‘right to silence’). The Court has, apparently, also held that even when a person volunteers to be subject to these tests, their result cannot be admitted as evidence in a court of law.
Prof. Mrinal Satish has written a note on the judgment which has been posted as a guest post on the Law and Legal Developments blog. The link which might be of interest to readers on this blog too, is:
http://legaldevelopments.blogspot.com/2010/05/prof-mrinal-satish-on-selvi-judgment.html
I Think Supreme Court Judgement came as a big blow to the top investigation agencies of the country, and many suspects in famous cases will make use of this judgment to escape.
http://www.lawisgreek.com/supreme-court-on-narco-analysis/