In the case of Smt. Selvi & Ors. v. State of Karnataka [Criminal appeal No. 1267 of 2004], a three judge bench of the Supreme Court observed that the compulsory administration of the techniques like narco analysis tests constitutes ‘cruel, inhuman or degrading treatment’ in the context of Article 21 of the Indian Constitution and narco analysis test cannot be forcibly conducted on anyone. The incredulity raised in respect of instances where individuals who were the accused, suspected or witnessed in an investigation had been subjected to these tests without their consent.
In this case, they were mainly considered with situations when investigators seek reliance on these tests to detect deception or to verify the truth of previous testimonies. Furthermore, litigation related to polygraph tests involved situations where suspects and defendants in criminal cases have sought reliance on them to demonstrate their innocence. It was also conceivable that witnesses could be compelled to undergo polygraph tests in order to test the credibility of their testimonies or to question their mental capacity or to even attack their character.
“The legal questions in this batch of criminal appeals relate to the involuntary administration of certain scientific techniques, namely narco analysis, polygraph examination and the Brain Electrical Activation Profile (BEAP) test for the purpose of improving investigation efforts in criminal cases. This issue has received considerable attention since it involves tensions between the desirability of efficient investigation and the preservation of individual liberties. Ordinarily the judicial task is that of evaluating the rival contentions in order to arrive at a sound conclusion. However, the present case is not an ordinary dispute between private parties. It raises pertinent questions about the meaning and scope of fundamental rights which are available to all citizens. Therefore, we must examine the implications of permitting the use of the impugned techniques in a variety of settings.”
“In the context of criminal cases, the reliability of scientific evidence bears a causal link with several dimensions of the right to a fair trial such as the requisite standard of proving guilt beyond reasonable doubt and the right of the accused to present a defence. We must be mindful of the fact that these requirements have long been recognised as components of ‘personal liberty’ under Article 21 of the Constitution. Hence it will be instructive to gather some insights about the admissibility of scientific evidence.”
“The court stressed on the three prominent polygraph examination techniques:
- The relevant-irrelevant (R-I) technique
- The control question (CQ) technique
- Directed Lie-Control (DLC) technique
Each of these techniques includes a pre-test interview during which the subject is acquainted with the test procedure and the examiner gathers the information which is needed to finalize the questions that are to be asked. However, we do leave room for the voluntary administration of the impugned techniques in the context of criminal justice, provided that certain safeguards are in place.”
It was held that no individual should be forcibly subjected to any of the techniques in question, whether in the context of investigation in criminal cases or otherwise.