(iv) Report of the Ballistic Expert on examination of the weapons
alleged to have been used by the deceased and his companions.39
II. Lie Detector Tests
The NHRC has laid down guidelines for the conduct of the Lie Detector
Test or polygraph test in view of the complaints that the police, without
explaining to people the full implications of a lie detector test, was making
them take it, in violation of their fundamental right and the fact that lie
detector or polygraph tests are not regulated by any particular law as such.
While issuing these guidelines, the NHRC followed the principle: in the
absence of a specific law, any intrusion into fundamental rights must be
struck down as constitutionally invidious [violative]. The NHRC said that
the invasiveness of a lie detector test overrules the argument of the police
that the authority to use lie detector tests comes from their powers under
the Code of Criminal Procedure [CrPC] to question and interrogate suspects
and stated that, holding of such tests is the prerogative of the individual
and not an empowerment of the police. It must perforce be regarded as
illegal and unconstitutional unless it is voluntarily undertaken under noncoercive circumstances.
Also, there is no scientific evidence to prove that results obtained from
polygraph tests are conclusive. Failing a lie-detector test does not mean that
the person is guilty. Polygraph tests measure responses on the premise, that
a person is being untruthful, if there are sudden changes in her/his breathing,
heart and blood pressure rates. A truthful person can fail the test if s/he is
nervous, has health problems or is just surprised by the question.
The Guidelines are as fallows 1.
2.
3.
4.
39
Lie detector tests must not be carried out without the consent of the
accused.
If the accused volunteers to take a lie detector test, s/he must be given
access to a lawyer to explain the physical, emotional and legal
implications of the test. The implications must also be explained by
the police.
Consent to take a lie detector test must be recorded before a Judicial
Magistrate.
The magistrate must take into account, the time the accused has been
in detention and the nature of her/his interrogation. This should be
Please see www.nhrc.nic.in - List of Important Instructions/Guidelines by the Commission
Manual on Human Rights for Police Officers
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