This Article focuses on legality of practicing of Narco Analysis Test. People on whom this test is conducted often allege it to be violation of their Right to Self-Incrimination guaranteed under Article 20(3) of the Constitution of India. This article analyzes whether such test is actually violating any such constitutional right or not, thereby testing its constitutional and legal validity.

What is Narco Analysis test?

Narco-Analysis test, also known as ‘Truth Serum Test’, is done with the main intent and aim of extracting information from the accused when he is in Hypnotic state. The test uses an Injection named Thiopentone, chemically called ‘Sodium Pentathol’ which is mixed with distilled water before injecting to the accused. The test is carried on for 1 -3 hours and after 15 minutes of the medication the person is perfectly normal.


THE HON’BLE  SUPREME COURTOF INDIA is of the view that Narco, Polygraph or Brain mapping tests cannot be conducted on any person,  whether  an accused or a suspect, without their consent.

The Court further stresses that no person should be compelled to go through such test as it amounts to violation of Art 21 i.e. Right to Personal Liberty  and prohibits Self-incrimination and thereby violates Art 20 (3). In short according to Supreme Court, conducting Narco Analysis Test is Unconstitutional and Illegal.

The author differs in views regarding the same. Looking at the pathetic contemporary situation having abundance of criminals and plenty of crime witnessed every other day and the number of innocent lives affected everyday owing to increasing rate of crime, it seems to be the high time to realise need of ways to check and minimise such crimes. Law plays an important role through various precedents and it should contribute proactively to bring forth ways to reduce crime.

Narco Analysis test, which is mainly carried out with the purpose of facilitating the investigating team to reach the evidence as soon as possible, has been used as a scientific tool for the investigation purpose.


For instance the Forensic Science Laboratory, Gandhinagar and The Bangalore Forensic Sciences Laboratory has successfully conducted various narco analysis tests since 2000.

Dr. B.M. Mohan, Director of FSL, Bangalore, claims that he has data of over 300 cases to prove his contention that Narco Analysis has shown a success arte of 96-97 per cent. It would be appreciable to ignore dark sides when clearly in majority of cases it has worked successfully.

I totally disagree that conducting Narco Analysis deprives a person’s right to personal life and liberty Art (21) and infringes the right against self-incrimination Art 20 (3). It should be viewed as a necessary step in order to province justice to the aggrieved or victim and a helpful step in investing a particular case.

The advances in science and technology must be used by the police to solve mysteries of crime and thereby for the benefit of society. It is atleast better option for investigation than the classical interrogation method involving third degree torture, where the accused breaks down and blurts out the truth.


And usually in most of the cases the innocents unable to bear the torture confesses to the crimes, they have not at all committed. Isn’t it a violation of one’s fundamental right and much graver violation? I don’t think that such painful and inhumane methods are better than Narco Analysis anyway.

The author doesn’t attempts to say that results of  Narco analysis test are very much realiable but results of such tests can be used to get  an admissible evidence, can be collaborated with other evidence or to support other evidence.

Before coming to any conclusion one must know what actually happens in this test. The drug used is known as PENTOTHANAL. It is harmful only when taken in high dose. The ECG and blood pressure have to be monitored.

The questions are designed carefully and are repeated persistently in order to reduce the ambiguities during drug interrogation. After the Narco-examination is over the suspect is made to relax for 2-3 hours. The report prepared by the experts is useful in the process of collecting the evidence. Expert psychologists, who frame the questions and guide the investigation process, conduct these tests in a controlled environment and ensure to reduce the margin of error to minimum.


As stated by the Supreme Court in  Dharampal and State of Gujrat v. Anirudh Singh  , that it is the statutory duty of every witness who has knowledge of the commission of the crime, to assist the State in giving evidence. So it seems justified that if the person does not willingly reveal such information that may be relevant to the investigation, an adverse impression must be taken against him. That is why the supporters of the test say that there is no conflict between Narco analysis and Article 20 (3) of the Constitution of India.

In case of US v Solomon , it was held that Narco Analysis is accepted as a investigative technique. The most recent of these cases has been Narco-analysis of Abu Salem in which he reportedly revealed many missing links of various cases he has been involved in.

Narco-Analysis Test and Article 20(3)-

After being aware of the procedure to conduct the test, one can better analyse whether it is violative of Article 20(3) RIGHT AGAINST SELF-INCRIMINATION.


The discussion on Article 20 (3) spells out three following requirements which must be met with, in order to claim protection under Article 20 (3). If any of these requirements is not met, Article 20 (3) cannot be invoked.

If Narco Analysis is carried out on an accused, it definitely fulfilsv the first requirement of Article 20 (3). However, the question is whether subjecting a suspect to such a test also fulfils the requirement of Article 20 (3).

Hence, I feel that if a person is suspected to have some information regarding the commission of an offence, there should be no prohibition on conducting a Narco Analysis test on him as the protection under Article 20 (3) is available only to a person accused of an offence.

Another requirement of Article 20 (3) is that there should be no compulsion. In fact, the Supreme Court in State of Bombay v Kathi Kalu Oghad , held that there is no compulsion when a police officer, in investigating a crime against, a certain individual, asks him to do a certain thing.


The mere questioning of an accused by a police officer, resulting in a voluntary statement, which may ultimately turn out to be incriminatory, is not compulsion. Considering, all these we can easily conclude that Narco Analysis does not violate Article 20 (3) to the extent that the person undergoing such a test is not compelled to do so, rather it is done with the consent of the person who has full knowledge of such a test.

The third requirement of Article 20 (3) is that the there should bev compulsion to give evidence against oneself. Only incriminatory statements are hit by Article 20(3). Whether a statement is incriminatory or not can be ascertained only after the test is conducted and not before it.

Hence, I do not see any reason to prohibit such a test. By conducting Narco Analysis, the investigating agencies might discover some information which will help them in the investigation of the crime and thus get hold of true culprit. The above discussion very clearly suggests that Narco Analysis test can be conducted without violating Article 20 (3).

Thus if the evidence is true, then there would be no reason why this Article 20(3) gets violated. Thereby it is said that if the test is done properly, after following all precautionary procedures, then Narco analysis, as a test will fall well within the spirit of The Constitution of India.

Narco analysis will act as a boon to the investigation procedure. Although it should not be made a matter of practice and should be used only in demanding situations. But today when narco-analysis is gaining judicial acceptances and supports despite being alleged as “unreliable & doubtful” science, serious thoughts have to be given about its legal and constitutional validity from human rights perspective.


Shubhda Payasi