LAHORE: The Lahore High Court has ruled that the polygraph test is a useful investigative technique to unearth the truth, but subject to the knowledge and expertise of the examiner.

In a verdict that acquitted a murder convict, Justice Muhammad Amjad Rafiq has observed that in the past there was criticism over the polygraph test as being inconclusive and an intrusion into personal liberty and fundamental right suggesting that it should not be conducted without consent.

However, he notes, there are some studies which show improvements in the accuracy of the results after advancement in technology.

The judge says objections can be raised about the qualifications and skills of the examiner, the physical conditions under which the test is conducted, the manner in which questions are framed and the possible use of `countermeasures` by the test subject.

He admits that a significant criticism of polygraph test is that sometimes the physiological responses triggered by feelings such as anxiety and fear could be misread. But it can be a best investigative tool to take a lead for collection of directevidence,thejudge adds.

Expressing dissatisfaction with the skills of the examiner who conducted the test of the convict/appellant, Justice Rafiq observes: `It is apparent that the expert has not taken much pain to ascertain the facts in issue while formulating question.

The judge regrets that the questions posed by the examiner in no case helped to detect lies or provide any additional information so as to add valuable contribution for building an opinion for and against the truthfulness of the accused.The judge observes: `The test must be explanatory not only to question relating tofactsin issue or relevantfacts but also for requiring some more information relating to crime.

Highlighting the techniques for a perfect attempt to extract truth through a polygraph test, Justice Rafiq refers to a judgement passed by the Supreme Court of India titled, `Selvi & Ors versus State of Karnataka & Anr on 5 May, 2010.

The techniques suggested in the Indian judgement are: the relevant-irrelevant (R-I) technique, the control question (CQ) technique and the Directed LieControl (DLC) technique.

The judge maintains that the prosecurion can make good use of the polygraph test provided it is conducted by a knowledgeable expert with formulation of sound and relevant questions following the three techniques in order to cover all areas of information relating to crime.

He says an objection can be raised that through polygraph test, a truth is extracted technically and sometimes by asking misleading questions, or through promise or without warning etc.

However, he adds, article 42 of the Qanun-i-Shahadat Order, 1984 (confession otherwise relevant not to become irrelevant because of promise of secrecy, etc), gives due legal cover to such arrangement.

The judge says, based on the available studies, the experts assess the accuracy of polygraph examinations administered by a competent examiner to be about90 percentasthelevelofskilland experience of the examiner plays an important part in the accuracy of the test results.

Allowing the appeal of convict Muhammad Aslam, the judge holds that the prosecution miserably failed to establish the charge against the accused beyond any shadow of doubt.

A trial court of Depalpur had awarded life imprisonment to the appellant on a murder charge.

The appellant was administered the polygraph test, but the examiner had not given any conclusive opinion as to his truthfulness due to, what he claimed, poor psychophysiological data.