New Delhi: The plea that scientific tests
would save an accused from the much-used third degree
custodial torture did not cut much ice with the Supreme Court,
which trashed it saying one wrong cannot be corrected by
"This is a circular line of reasoning since one form of
improper behaviour is sought to be replaced by another," a
bench, headed by Chief Justice K G Balakrishnan, said.
It disapproved the "perceivable notion" that allowing use
of such techniques (polygraph tests, narco and brain
mapping) could reduce the high incidence of "third degree
method" being used by police all over the country.
The apex court, in its landmark ruling on the issue,
termed such forcible administration of any of the techniques
as "an unjustified intrusion into the mental privacy of an
It said such luxury, granted to probe agencies, would
amount to dilution of Constitutional protection of a person
against self incrimination.
"The invocations of a compelling public interest cannot
justify the dilution of Constitutional rights of right against
self-incrimination,” the bench, also comprising Justices
R V Raveendran and J M Panchal, said.
It would also amount to `cruel, inhuman or degrading
treatment` with regard to the evolving international human
rights norms. Furthermore, placing reliance on the results
gathered from these techniques comes into conflict with the
right to fair trial, the court said.
These tests were still evolving and the interpretation of
the results was a complex process involving accounting for
distortions used by the accused (subject of test) and the
weather conditions, it said.
"In a narco-analysis test the subject is likely to divulge
a lot of irrelevant and incoherent information. The subject is
as likely to divulge false information as he/she is likely to
reveal useful facts. In a polygraph test, interpreting the
results is a complex process. In a BEAP (brain mapping) test,
there is always the possibility of the subject having had
prior exposure to the `probes` that are used as stimuli," the
The court said it was beyond its judicial authority to
permit qualified use of the techniques by probe agencies.
"We do not have the authority to permit the qualified use
of these techniques by way of enumerating the offences which
warrant their use. By itself, permitting such qualified use
would amount to a lawmaking function which is clearly outside
the judicial domain," the court said.