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Subham Saurabh and Nikita Sharma, IV year of B.B.A.,LL.B.(Hons.) from Himachal Pradesh National Law University, Shimla


Admission of self-incriminatory statements is the best thing that can happen in a criminal trial for it speeds up justice. However, history reveals that when such self-incriminatory statements are made it is less due to repentance and more because of police or other pressure which often lead to imprisonment of an innocent man. Paying recognition to this history and utter realities of life, the makers of our constitution sought to make a special provision against involuntary self-incrimination by accused. The importance of which is brought out by the fact that it was not left by them to be dealt in CrPC or other criminal legislation but was considered necessary enough to be incorporated in the constitution as Article 20 (3).

While the constitution was made to be the supreme authority it was recognised by the makers that the future may hold unforeseeable possibilities. One of such being in this context Deception Detector Tests. While it is completely applauded able that involuntary self-incriminatory statements should be frowned upon for, they imply torture, one fails to comply with that reason when it comes to lying detector tests. In that light should these be permitted to be used as a means of investigation?

Types of DDTs

One of the most popular kinds of such tests is Narco-investigation. It includes the intravenous administration of a medication that makes the person go into different phases of anaesthesia. In the hypnotic stage, the person turns out to be less restrained and is bound to disclose data, which would for the most part not be disclosed by him/her in the conscious state.[1] The person may likewise uncover all his/her dreams, individual wishes, driving forces, and so on. The principle drawback of this procedure is that a few people can hold their capacity to trick even in the hypnotic stage, while others can turn out to be very suggestible to addressing.

Another sort of test is the polygraph tests. Here the subject is probably going to be worried about lying about the significant facts about the wrongdoing by him/her, which thus delivers a hyper-arousal state which is picked by an expert prepared in perusing polygraph results. It is again not precise since results might be delivered by apprehension, tension and so forth.[2]At that point, we have Brain Mapping which depends on the finding that the cerebrum produces a brain-wave design when the person experiences a recognizable improvement.

Are these tests Legal?

The guidelines of guaranteeing fundamental reasonableness and fairness are that the person accused will not be indicted upon coerced or involuntary confession. Augmentation of this standard has led to the holding that proof/evidence got through force or by means which ‘shock the conscience will be unacceptable. In consideration to the above question, we can see three of our most fundamental rights being exposed and infringed, that is

1. Article 20 (3) which frowns upon involuntary self-incrimination. It reads simply as: “No person accused of any offence shall be compelled to be a witness against himself”

2. Article 21- Right to Dignity. It is criticised that using such means is inhuman and undignified and so volatile of Article 21 of the constitution.

3. Article 21- Right to Privacy which implies that it is an inherent right of a being to remain silent.

DDT additionally raises genuine concerns identified with the professional ethics of medical personnel associated with the organization of these procedures and infringement of human rights of a person. Concerns concerning human rights infringement in directing DDTs were raised long back and the National Human Rights Commission had made Guidelines in the year 2000 itself for the Administration of Polygraph tests.[3]However, as a general trend only a few of the administrative offices and investigating agencies seem to follow those rules.

Fortunately, we have an apt ruling from the Apex Court which deals with the interplay and reproduces the law on the question. The judgements which were delivered by the judges’ honourable bench namely K.G. Balakrishnan C.J.I and R.V. Raveendran J. and J.M. Panchal J. The Supreme Court mainly on the grounds founded upon the rights conferred by Article 20(3) came to this trendsetting landmark judgement, namely, Selvi v. State of Karnataka[4], it was held that:

“In our considered opinion, the compulsory administration of the impugned techniques violates the ‘right against self-incrimination’. It was held that this is because the underlying rationale of the said right is to ensure the reliability as well as voluntariness of statements that are admitted as evidence. This Court has recognised that the protective scope of Article 20(3) extends to the investigative stage in criminal cases and when reading with Section 161(2) of the Code of Criminal Procedure, 1973 it protects accused persons, suspects as well as witnesses who are examined during an investigation. The test results cannot be admitted in evidence if they have been obtained through the use of compulsion. Article 20(3) protects an individual’s choice between speaking and remaining silent, irrespective of whether the subsequent testimony proves to be inculpatory or exculpatory. Article 20(3) aims to prevent the forcible ’conveyance of personal knowledge that is relevant to the facts in issue’. The results obtained from each of the impugned tests bear a ‘testimonial’ character and they cannot be categorised as material evidence.”

It was additionally perceived that constraining a person to experience any of the impugned methods disregards the norm of ‘substantive due process’ which is required for controlling individual freedom. Such an infringement will transpire independently of whether these techniques are coercively regulated for an investigation or for some other reason since the test outcomes could likewise open an individual to unfavourable results of a non-penal nature.

Likewise, the impugned methods can’t add something extra to the legal provision which empowers medical assessment during examination in criminal cases, for example, the Explanation to Sections 53, 53-An and 54 of the Code of Criminal Procedure, 1973. Such an expansive translation isn’t possible considering the standard of ‘ejusdem generis’ and the contemplations which administer the understanding of rules comparable to scientific progressions. Moreover, putting dependence on the outcomes assembled from these methods clashes with the ‘right to a fair trial’. Summons of a convincing open intrigue can’t legitimize the weakening of constitutional freedoms such as the ‘right against self-incrimination’ etc.[5]

Important is that in any event, when the subject has offered to agree to experience any of these tests, the test results by themselves can’t be conceded as proof because the subject doesn’t exercise conscious command over the reactions during the functioning of the test. Notwithstanding, any information or material that is in this way found with the assistance of voluntary administered test results can be admitted, as per Section 27 of the Evidence Act, 1872.[6]

Concluding Remarks

Finally, it tends to be said that no individual ought to be persuasively exposed to any of the methods/techniques being referred to, regardless of whether in the regards to investigation in criminal cases or something else. Doing so would add up to an unjustifiable intrusion into individual freedom and personal liberty. Nonetheless, willful administration of the impugned methods might be done with specific safeguards set up.

It must not be forgotten that there exists a very strong argument put up by a large section of society and that is that if the procedure is safe and there are no negative mental and physical consequences then there seems to be no reason to not subject accused to these tests even against their will. It is highlighted that the complete jurisprudence against involuntary self-incrimination was developed because police force was misused in inhumane ways to compel accused to make, many times false, incriminatory statements. However, with the use of a medical procedure that possibility is obviated. What remains then the reason to prescribe these procedures irrespective of the fact that these are involuntary?

It should not be forgotten that we have a system which requires proving guilt beyond reasonable doubt to hold a valid conviction. Justice Nariman in his book[7] says our system should move to a truth-finding approach. If these medical procedures only help us find the truth, there should not be any argument against it.

Anyways, any incriminatory statement can never be made sole basis of conviction. So, let us say that a person admits guilt but there is no other convincing evidence against him, he cannot be convicted merely because he made a self-incriminatory statement. This is one of the established principles of law. Such statements can only be used circumstantially and not direct evidence. Thus, these statements would still need a high degree of corroboration which leaves an accused only with a great amount of refuge. Not only this, but it also is not important that an incriminatory statement may be made, there may be cases where the accused may make statements revealing evidence of great importance or any such additional information about such evidence against himself or others.

The reality, however, remains that this is not yet achieved and there are moral questions on its being used. The authors, however, concur with Justice Nariman and submit that it is time that we move to truth-finding exercise rather than this game of adversarial system. Do we do that by making an involuntary subjection to DDT's? This is a question which the judiciary has for now answered in negative.

[1]Suresh BadaMath. “Supreme Court judgment on polygraph, narco-analysis & brain-mapping: a boon or a bane” The Indian journal of medical research, 134,1 (2011) pg. 4-7.

[2]Lefebvre CD, Marchand Y, Smith SM, Connolly JF. “Use of event-related brain potentials (ERPs) to assess eyewitness accuracy and deception” International JournalPsychophysiol, 73:218 (2009) pg. 25.

[3]National Human Rights Commission. NHRC Guidelines. available at . [accessed on July 10, 2020].

[4]AIR 2010 S.C. 1974.

[5]Selvi v. State of Karnataka, AIR 2010 SC 1974.

[6]See:D.K. Basu v. State of West Bengal, A.I.R. 1997 S.C. 610.

[7]FALI S NARIMAN, INDIA’S LEGAL SYSTEM: CAN IT BE SAVED (1st ed., Penguin Books, 2006).


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