Court equates brain-map,narco-test

Brain-mapping and lie-detector tests merely watch the physical fluctuations of a criminal suspect to help investigators detect a lie....

Brain-mapping and lie-detector tests merely watch the physical fluctuations of a criminal suspect to help investigators detect a lie. Unlike narco-analysis,not a word is exchanged between the suspect and the interrogator during the entire period of the tests,but the Supreme Court on Wednesday chose to ban the forcible use of the two probe tools used extensively by investigative agencies like the Central Bureau of Investigation.

While the bench was sure about the illegality of the involuntary use of narco-tests as the procedure substantially relies on verbal statements,it admits to have entered a grey area,with no written law to support,as far as brain-mapping and lie-detector tests goes.

Initially in the judgment,the Supreme Court bench led by Chief Justice K G Balakrishnan agrees with the government,which had argued that brain-mapping or Brain Electrical Activation Profile BEAP test or polygraph lie-detector examination improve and quicken criminal investigations.

The results obtained from polygraph examination or a BEAP test are not in the nature of oral or written statements. Instead,inferences are drawn from the measurement of physiological responses recorded during the performance of these tests, the court agrees with the government.

The bench then records Solicitor General G E Vahanvatis argument that the two tests were not intrusive on the suspects as they do not involve a positive volitional act on part of the test subjects. The results should not even be treated as testimony admissible in court,but purely to aid the police during investigations,the government had pressed on.

The bench said the courts have till date been silent on the legality of other interrogative methods which did not involve imparting knowledge about a relevant fact through silence.

The difficulty arises since the majority opinion appears to confine the understanding of personal testimony to the conveyance of personal knowledge through oral or written statements. The results obtained from polygraph examination or a BEAP test are not in the nature of oral or written statements, the court observes.

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So,the court introduces a crucial test,that of common sense,to check the validity of the governments stand.

Common sense dictates that certain communicative gestures such as pointing or nodding can also convey personal knowledge about a relevant fact,without offering a verbal response. It is quite foreseeable that such a communicative gesture may by itself expose a person to criminal charges or penalties or furnish a link in the chain of evidence needed for prosecution, the court says.

Such personal knowledge about relevant facts can also be communicated through means other than oral or written statements, the court observes.

Privilege to not communicate not only extends to verbal communications,but also to written words and gestures intended to communicate, the court lays the law by equating brain-mapping and polygraph examination with narco-analysis test.