The apex court further observed that these tests are in contravention of the right to silence that an accused enjoyed. The Law Commission in its 108th report specifically warned the government against any dilution of right to silence in view of such trends in countries like UK. While dismissing the pleas of various state governments that the scientific methods should be supported in public interest for efficient investigation of criminal cases, the court said that “questionable scientific reliability of these techniques comes into conflict with the standard of proof ‘beyond reasonable doubt’, which is an essential feature of criminal trials”. The Court further observed that “If we permit the forcible administration of these techniques, it could be the first step on a very slippery slope far as the standards of police behaviour are concerned.”
The judgment, as expected, has evoked critical response from police investigators and approbation from lawyers and human rights activists. Some senior police investigators are of the view that use of these techniques provides useful and critical leads in some cases. In Telgi Stamps scandal narco analysis, according to some CBI officers, did provide useful leads. Now as far as the CBI is concerned the investigation in several cases where narco tests are pending would be hit. In Arushi case, the CBI took the permission of the Talwar couple before conducting test on them. It seeks the Court’s consent only when suspect refuses to undergo narco analysis and investigators feel that it is crucial. Now refusal by the suspects would end the matter. After the Supreme Court verdict, the main accused in Ajmer Blast case Devendra Gupta has filed a petition in the local court seeking exemption from this test. Lawyers and Civil rights groups however have welcomed the judgment. Mumbai based senior lawyer Majid Memon has said that the judgment is important in the context of our country where many a time poor and innocent people are forced to speak against themselves. Lawyer Prashant Bhusan has dubbed narco analysis as a very “imperfect and hazardous procedure which gives incorrect information.”
Efficacy of narco analysis and other tests is often over-stressed by the police. The police are misguided to think the narco analysis is a boon to the police to make breakthroughs. The technique is neither modern nor an internationally accepted one. Narco analysis first captured attention when Robert House, a Texas obstetrician, used the drug "scopolamine" on two prisoners. These drugs are supposed to relax the individual defenses to the extent that he unwillingly reveals the truth he has been trying to conceal. Drugs like barbiturates, sodium pentothal have become the drugs of choice. But by 1950s many scientists declared the notion of "truth serum" as invalid and many courts have ruled that testimony gained through them as inadmissible. It is true that barbiturates by disrupting defensive patterns can be somewhat helpful in interrogation, but even under the best of conditions they will elicit an output contaminated by deception, fantasy and garbled speech. According to a well-known forensic expert with considerable experience in participating in truth serum tests, these tests are occasionally effective on person who if they have been properly interrogated would have revealed the truth. On the other hand, the person who indulged in falsehood will be able to continue the deception even after the effects of the drug. Further wrong doses can send the subject into coma or even result in death.
Polygraph and Brain mapping Tests
Apart from narco tests, there are two other kinds of tests, which are popularly used on suspects for extraction of truth, namely, polygraph and brain mapping tests. In polygraph test, the machine records the blood pressure, pulse rate and other bodily changes that are affected by a person’s emotional conditions. Recorded changes are then studied, analyzed and co-related in response to specific questions and other stimuli. Results obtained from polygraph tests are not very credible as the device measures, body’s reaction to different types of questions. The test is not scientific and "inherently biased against the truthful."
Brain mapping test developed and patented in 1995 by neurologist Lawrence Farewell, is claimed to be an alternative to polygraph test. Here the subject is first interrogated to find out whether is concealing any information. Then sensors are attached to the subject’s head and the person is seated before a computer monitor. He is then shown certain images or made to hear certain sounds. The sensors monitor electrical activity in the brain and register p300 waves, which are generated only if the subject has connection with the stimulus that is picture or sound. The subject is not asked any questions here. In America, the Federal Bureau of Investigation has been making use of “brain mapping technique" in Criminal investigations.
This verdict of the Supreme Court now poses a challenge for police investigators and law enforcement officers. They will have to rely on diligent, painstaking investigation to unearth crimes and detect the criminals. The apex Court in this case has also pointed out that though the arguments on public safety “merit consideration”; it is the task of the legislature to arrive at a “pragmatic balance between the competing interests of personal liberty of the accused and public safety.”
