Selvi Vs State of Karnataka – Case Analysis


“All human beings got three lives: public, private, and secret.”

    ― Gabriel Garcia Marquez.

Privacy is something whose worth can be, at times, tough to measure. It is priceless in a word. Private life is meant to be private, not public, which clearly desires no intrusion. Breach of the right to privacy, even in the case of desirable and wanted intrusions, could pose an immeasurable loss to a party suffering the consequences of such breach.[1] In the aforesaid judgment of Selvi Vs State of Karnataka (2010) 7 SCC 263, the constitutionality of various evidence-collecting techniques was challenged in the terms that such techniques are highly affecting the accused’s right to privacy in the event of the application of such techniques to extract their testimonial from them when they voluntarily deny aiding the enforcement agency with their crucial statements subject to the crime committed. Such a means of extracting testimonials through neuroscientific investigative technique has been criticized in the concerned judgment as being violative of Article 20(3) (Right to be protected against self-incrimination) as also Article 21; more specifically, it is in breach of the right to privacy of the accused. Prominence has been provided to the mental privacy of the accused within the purview of the jurisprudence of the right to privacy. An assertion has been raised post this judgment relating to the extension of the protection against self-incrimination towards including the right to a fair trial within the ambit of Article 21 of the Constitution and shall not be confined only to the courtroom but shall also extend to the prosecution.

Facts of Selvi Vs State of Karnataka Case

The facts of this case state that the appellant Selvi’s daughter married a man from a different caste against her family’s wishes. In 2004, the man was brutally murdered, and Selvi and two others became the prime suspects. In this case, the prosecution sought the Court’s permission to conduct polygraph and brain mapping tests on the three suspects and such permission was granted. However, when the results of these tests showed deception, the prosecution sought permission to conduct narcoanalysis on the three persons, which the Magistrate granted. The three suspects challenged this decision at the Karnataka High Court but were denied relief. The appellants, being aggrieved, then appealed to the Supreme Court. In 2004, the appellants filed the first batch of criminal appeals at the Supreme Court; thereafter, successive appeals in the year 2005, 2006 and 2007 and 2010 were filed, which were taken up together through a special leave petition on 5th May 2010. In this present batch of criminal appeals, the primary objection that the appellants raised was in respect of the instances wherein the accused, suspects or witnesses in an investigation are expected to go through the neuroscientific investigative techniques without even bothering to take their consents.

Issues Raised

  1. Whether the results derived from the neuroscientific investigative techniques amount to compulsive testimonials, which in turn is contrary to the sense of protection provided against self-incrimination?
  2. Whether the involuntary administration of the neuroscientific investigative techniques could be considered to be a reasonable restriction on ‘personal liberty’ justified by law when interpreted in the context of the provisions provided under Article 21 of the Constitution?
  1. Whether the involuntary administration of neuroscientific investigative techniques violates the right against self-incrimination as enumerated in Article 20(3) of the Constitution?
  1. Whether the use of neuroscientific investigative techniques has the effect of self-incriminating the test subject?

The Contention of the Parties

The appellants raised arguments invoking the guarantee of ‘substantive due process’ as an extension of ‘personal liberty’ protected by Article 21. The appellants submitted that the involuntary administration of neuro-scientific techniques violated the ‘right against self-incrimination’ under Article 20(3) for those compelled to use them. The appellants also argued that Article 21 includes a right against inhuman treatment and that the involuntary administration of the neuroscientific investigative techniques would violate such rights. Finally, they also raised the issue of the test subjects’ right to both physical and mental privacy and argued that the techniques in question would violate the same.


In relation to the tests themselves, the appellants argued that the tests were not scientifically valid but were only confirmatory and that evidence gathered through them could not be relied upon. They placed reliance on empirical studies, which cast doubt on the reliability of evidence obtained through these mechanisms.

The respondents argued that such tests were necessary to extract information that could help the investigating agencies prevent criminal activities and gather evidence. They also argued that administering such tests in a human body is devoid of any harm and that the extracted information was used only for investigation and not as evidence during the trial stage.

Judgment of Selvi Vs State of Karnataka

The Supreme Court held that the protective provision of Article 20(3) against self-incrimination extends to the investigative stage in criminal cases. The Court held that the compulsory administration of the neuroscientific investigative techniques should essentially be considered violating the right of an accused, suspect or witness against self-incrimination. It is because the emphasis is provided on the reliability and the voluntariness of the statements that could be admitted as evidence while conducting the investigative techniques. Moreover, Article 20(3), when read alongside Section 161(2) of CrPC, briefly explains the protection’s extension to the individuals subject to examination during an investigation. It was further observed that the test results obtained could not be admitted as evidence if it is revealed that they have been obtained by infliction of compulsion or coercive means.


Article 20(3) protects an individual’s choice to speak or remain silent, irrespective of the fact whether the subsequent testimony proves to be inculpatory or exculpatory. In a word, it is meant to provide prominence to the mental privacy of an individual. To exert coercive means upon an individual to undergo any of the neuroscientific techniques grossly breaches the standard of due process, which is enough to restrain the personal liberty of an individual.

It has been considered that a compulsory administration of any of these techniques is meant to be an unjustified encroachment into the mental privacy of an individual. It is unjustified to forcibly ask an individual to participate in any of these techniques in question, even in regard to investigating criminal cases or otherwise. Therefore, coercion of such a nature shall amount to an unwarranted intrusion into personal liberty. Considering contemporary international human rights policy and guidelines, it would also amount to inhuman treatment.

Although the subject has given consent to undergo the neuroscientific techniques of investigation, such test results could not be admitted as evidence owing to the fact that in the course of conducting such tests, the subject did not apply any conscious control over his responses to the tests. On the contrary, under Section 27 of the Evidence Act 1872, if any information or material is extracted with the help of a voluntarily administered test, that can be admitted as evidence. However, the court has left some room for the voluntary administration of neuroscientific investigation techniques in regard to criminal cases, which shall be admitted as evidence, provided that certain safeguards are maintained in conducting such techniques.


Critical Analysis of Selvi Vs State of Karnataka

In this case, it seems that the judges had emphasized the right against self-incrimination provided under Article 20(3). However, they did not focus more on the minority aspect, i.e. right to privacy. So, the focus must have been on the right to privacy to balance the situation. First, the reasons behind this are that different High Courts have constantly challenged the right against self-incrimination in different cases. Secondly, the violation of the right to privacy in the present case has been established beyond a reasonable doubt. The judgement starts with describing different forms of the right to privacy, but at the end of the case, it seems more inclined towards the concept of the right against self-incrimination.

In this case, judges have covered two important aspects of the constitution- The right to Privacy (Article 21) and the Right against Self-Incrimination (Article 20(3)). In India, this entire topic of privacy has always been undervalued. The judges, in this case, had to rely upon foreign judgements as a reference while deciding the case, as no such landmark judgements are available in India. Even if different High Courts decide some cases, they cannot be cited as the authority. From time to time, those cases have been challenged in other High Courts, and somehow contradictory judgements are available, making the situation more confusing and delusional. For example, the High Courts of Karnataka and Delhi had narrowed down the understanding of narco analysis by holding that these statements given by the accused cannot be a violation of Article 20(3) because these statements are not known to the accused, and he would get to know only after the administration of the test.

Exceptionally, in this case, in the course of establishing the theory of natural justice, the Supreme Court has observed that the utilization of neuroscientific techniques such as brain mapping, narco analysis, and polygraph tests on an individual recognised as an accused, witnesses and suspects without their consent shall be considered to be an unconstitutional approach and violation of their ‘right to privacy’. Thus, Supreme Court finally cleared the situation with this decision.


Although, by virtue of Section 161(1) of CrPC, the investigating officer has the full authority to examine any person orally who is supposed to be well aware of the facts and circumstances of the case. The fact which has to be noted here is that such an arrangement is here to ensure the citizens’ cooperation and participation in the investigation so police authorities cannot override the constitutional protections given to accused persons. Supreme Court, in the landmark case of Maneka Gandhi v. Union of India, wherein the airport authorities confiscated the passports without giving her any reasonable notice, held that the right to privacy is an essential ingredient to constitute personal liberty under Article 21 of the Constitution which shall, in turn, is comprised of the right of an individual to be liberated from restrictions or encroachments into his life, even though, calculated measures directly or indirectly impose those restrictions or encroachments.[2] The right to privacy, including the right to be not treated as inhuman and the right to a fair trial, is also an essential component of personal liberty.


The sociological school of jurisprudence establishes that social interest will be protected in case of conflict between social and individual interests. From the detailed study of the present case, it can be argued that the protection under Article 20(3) of the Constitution should not be extended in such a way as to hamper the social interest. Hence, tests like narco-analysis, brain mapping and polygraph tests should not be brought within the purview of Article 20(3) of The Constitution of India so as to hamper the social interest. Also, the right against self-incrimination establishes that the accused person is giving a statement against himself and is not even asked for consent. It is going to implant wrong ideals in the current progressive societies.

Therefore, with reference to the proliferation of crimes against society, it is necessary to keep in mind the necessity of the society at large and the need for a thorough and proper investigation of individual rights while ensuring that constitutional rights are not infringed. Law is a living process that changes according to society, science, ethics and so on. The legal system should imbibe scientific developments and advances as long as they do not violate fundamental legal principles and are for the good of society. The criminal justice system should be based on just and equitable principles.[3]


Henceforth, it can be conveniently derived that even the scientific techniques of polygraph and narco-analysis also have specific restrictions, and there is a scope for errors. Also, it can be said that since these tests are used to record the change in the physiological responses, instead of that, when these tests are conducted involuntarily on the accused without his consent, it generally leads to the emotions such as fear, anxiety, and confusion. The accused’s mental state generally produces highly abnormal physiological responses, which might mislead the examiner. The Supreme Court, by this prolonged judgement, held that Polygraph, Brain-mapping and Narco-analysis are cruel, inhuman and degrading treatment and thus cannot be permitted.

[1]State of Bombay v. Kathikalu, AIR 1961 Cri LJ, Vol 2, 2007.

[2] 1978 AIR 597.


[3] The litmus test, available at, last accessed on 11/3/2015.

Amrapali Mukherjee

I have completed my Masters in Commercial and Corporate Law from the Queen Mary University of London with upper merit and a distinction in the dissertation, currently, I am working as a Legal Advisor for a partnership firm at Kolkata.