Insanity As An Exception To Criminal Liability


The defence of insanity has existed for many decades, but it has only taken a legal situation for the past three centuries. Different measures were utilised to deem a person legally insane, like the Wild Beast test, the Insane Delusion test, and the “capacity test to vary between right and wrong.” These 3 tests provided the basis for the Mc Naughten law.

The general exceptions are given by IPC as mens rea is absent in some actions. Because of the separate, persuasive case, the act occurred. The basic rule is that it is assumed that the individual knows the essence and effect of the act. The general exceptions to criminal liability are dealt in Chapter IV of the Indian Penal Code. In the situations referred to in Sections 76 to 106, there are different categories of exceptions which do not equate to offences under the Code.

Section 84 of the IPC concerned with insanity explicitly expresses a basic concept of criminal jurisprudence, i.e. (a) “Actus nonfacit reum nisi mens sit rea” (unless performed with a guilty motive, an action does not imply guilt) and (b)”Furiosi nulla voluntas est” (mental illness person has restrictive will).

This suggests that unless performed with a guilty motive called “mens rea,” an act does not result in criminal charges. Therefore, since they don’t have reasonable thought or the requisite guilty intent, Section 84 IPC tightens no blame on individuals with mental illness.
The unsoundness of mind should be such that the defendant is extremely not competent to comprehend the essence of the act. The aspect that the individual suffers from a mental disorder is not enough in itself to suggest that he is mad. Under Indian law, in Section 84 of the IPC, the justification of insanity as a defence is introduced and is centered on the “Mc’Naughten’s Rule.” In its 42nd review, the Law Commission of India made an attempt to re-evaluate Section 84, and no changes were done. So at the time of the crime, it depends to the victim to justify his insanity.


The IPC’s ‘General Exceptions’ are discussed in Chapter IV of the IPC. This chapter, regulated by Sections 76 to 106, exempts’ persons from the criminal liability levied on them, subject to the fact that their activities are protected by general exceptions. In other terms, a person who committed an offence can avoid liability by the application of general exemptions.

This study explores the roots of IPC section 84, which under English law, is based on the McNaughton rule. In addition, this paper discusses the legal and medical insanity in relation to each other and this study also aims to communicate with various measures to assess an individual’s insanity.

While as per the law commission there is no need for reform, there is still a well-recognized fact that there is a scope for improvement in current laws as we exist in an ever-changing society.

The word unsoundness of mind is descriptively discussed in this article. The words’ unsoundness of mind ‘and’ psychosis ‘is basically similar, because we’re all conscious, and can be utilized interchangeably. Literally, this study focuses on the comprehensive definition of a person’s responsibility that is of unsound mind in criminal cases.

This is a well criminal law theory that there are ultimately two elements that need to be developed to demonstrate him guilty of a crime, namely Mens Rea and Actus Reus. The legal maxim Actus Non-Facet Reum Nisi Mens sit Rea suggests to prove a crime,’ the act and the purpose must overcome together.’

Insanity Section 84:

The act of an unsound person’s mind- “Nothing is an offence which is done by a person who at that time of performing it, by reason of unsoundness of mind, is incapable of knowing the nature of the act, or that he is doing what is either wrong or contrary to law.”

The essentials of Section 84 are:

  1. The individual must be of an unsound mind,
  2. The individual must be unable of assessing the
    • act’s nature
    • act contrary to the law
    • act has become inadmissible

M’Naghten Case

The most important landmark in the law of insanity history is this case. The case is notable because it motivated values and revolt as a response to its questionable decision. The case has the assassination of Mr. Edmond Drummond, who was the personal secretary of the then England PM, Sir Robert Peel. Mr. DenielM’Nathten, under the assumption that he was indeed Mr. Peel, fatally shot Mr. Edmond. In his mistaken conviction that Mr. Peel had hurt him, his desire to kill Mr. Peel had its roots. He was convicted on the charges of insanity by the court.

The medical evidence revealed that because of a state of morbid insanity, Mr. Edburn was not under his power. Mr. M’Naghten’s conviction and his acquittal generated a disturbance. Because of the furor over his acquittal and the perceived uncertainty in the laws on legal insanity, 5 questions were formulated and addressed to 15 judges by the House of Lords in order to seek clarity on the rules surrounding a claim of legal insanity. What is pointed to as the M’Naghten Rules on legal insanity is nothing but the composite version and the solutions to these issues.

M’Naghten Rules

The M’Naghten Rules can be summarised in the form of the following 5 propositions:

1. Every individual is assumed to have a sound mind and to be able to possess the mental ability to be responsible for his or her criminal actions. If the opposite is claimed, the burden of proof is on the person who argues it.

2. To be excluded from the criminal responsibility of an action, it has to be shown that at the time of doing the action, the individual was not aware of the essence and quality of the act he was doing because of a defect of the mind, or if he knew it, he did not realise that what he was doing was wrong.

3. At the time of doing the act, if a person was aware of the circumstance that he shouldn’t have done the action or that his act was opposite to the law of land, he should be ruled criminally responsible.

4. In the problem of the insanity of the suspect on the facts presented him, a medical witness who may not have previous information of the victim before the trial should not be urged.

5. If a person commits such actions because of delusional insanity and therefore not understanding the exact essence of his acts, if his action is judged in light of the truth believed by him, he would be made responsible to the same extent as he would be.

Wild Beast Theory in the Case of R v Arnold

In this scenario, Tracy J. suggested the hypothesis that has come to be recognised as the ‘wild beast theory’ to establish the precise type of mental defect that should be excluded from criminal responsibility. He argued that not every strange in the actions of a man can be excluded on the grounds of insanity. He believed that the perception of a man is really no more than a child or a wild beast in to be protected from criminal prosecution and thus unable of discriminating between good and bad.

The Delusion Test in the Hadfied Case

In this case, the defence counsel was successful in persuading the jury that if knowing, the claim of insanity can’t be limited to complete misery. He suggested that the insanity test must also take into consideration established insane delusions that exist only within particular circumstances and do not impact the individual’s total character in full.

Bowler’s Case of Right and Wrong

This case saw a divergence from the philosophical paradigm of ‘good and bad’ to the concept of ‘right and wrong’. The measure of insanity was therefore held to be centered on the ability of man to discern between right and wrong. Though Lord Mansfield C.J., in the case used the term ‘right and wrong’ considered synonymous with ‘good and bad,’ this case prompted a pattern where the courts began to put more focus on the definition of ‘right and wrong’ in subsequent cases.

Durham Rule

In order to assess insanity as outdated, the case of Durham v. United States ruled all the other predominant tests and indicated that other tests must be removed, and hence the federal judges proposed a new rule known as the Durham rule to determine insanity. This rule is one of the attest tests on the insanity test since this rule takes into consideration the causal relation between the action taken and the accused’s mental state of mind, and this approach is a rational approach and correctly refuses the presence of any abnormal aspect as a factor that induces insanity.

Tests or principles to evaluate a person’s insanity

It should be seen that at the moment of the offence, the accused was of an unsound mind. If at the moment, he was not insane but then became insane, he could not take advantage of Insanity as exception.

Queen-Empress v. Gedka Gowala: History of prior insanity, the actions of the defendant incident day, the nature of his mind prior to the actual commission of the crime are essential considerations to be taken into account. Proof of pre-meditation, confidentiality, motive, an effort to resist arrest, statement given on the very next day, etc for example, can make the insanity defence untenable.

Queen-Empress v. K.N. Shah: What are covered by Sec. 84 are mental cognitive faculties that are inherently damaged, i.e. innate or organic incapacity. Insane actions are not a defence because cognitive skills are not compromised and only will and emotions are impacted.

Lakshmi v. State: It is not that an individual should not realize that an action is right or wrong to assert immunity under Sec. 84, but that he’d be unable to know if the action performed by him is right or wrong. When it is known that the ability to differentiate between right and wrong is still flickering, under Sec. 84, a man can’t be covered.

Ahmed v. King: The suspect assassinated his own 5-year-old son by pushing a knife under the misconception in his throat and following an order given to him in his dream by others in paradise. Under Sec. 84, he was held to be secured.

Paras Ram v. State of Punjab: In a case in which a father and his family offered a 4-year-old son to make offerings to a god, the Supreme Court ruled that this didn’t establish insanity on its own.

Where, for no known cause, actions of violence are performed by a person, killing his own friends and neighbours to those he has been loved up all along, and where the individual has a prior history of lunacy, the benefit of doubt works in his support.

Persons that are sometimes attacked by ghosts and others who are most frequently conjured up visions in fits of delirium are granted the advantage of Sec. 84. But if the patient knew what he’s doing, he would’ve been criminally liable in instances of delirium tremens, some kind of insanity caused by recurrent extreme liquor or disease.

Unsoundness of Mind

It is necessary to remember that at the time of executing the offence that matters, it is unsoundness of mind and any unsoundness of mind prior to or beyond the commission of the crime does not provide the security of section 84. In assessing the state of mind of the accused, situations before and after the crime may be appropriate but are not applicable for the reasons of the section 84 applicability.
The word insanity incorporates in its fold many mental situations. For the purposes of Section 84, however the only form of insanity that arises is a cognitive disability that makes him unable to comprehend the meaning of his conduct or to understand that he is doing something wrong or contrary to law.


The study will clearly demonstrate that the McNaughton Rule forms the basis of the law relating to the criminal liability of an individual in India with an unsound mind. This article provides a contrasting account of the law of insanity (as applied to in the UK) and the law of unsoundness of mind (as referred under Indian law). In order to support this, the best possible approach was put in place to perform an in-depth review together with different case laws and authorities. Furthermore, it can be said that it is the responsibility of the Law Commission of India to take appropriate steps to amend the clause. In order to stop its abuse, the unsoundness of mind law or in other words, Section 84 of the Indian Penal Code requires to be viewed again to address the loop holes in the law in line with the changing time and society needs.

This article has been written by Chidige Sai Varshitha, student at Damodaram Sanjivayya National Law University.

Also Read – Provisions of Cr.P.C Relating to the Persons of Unsound Mind

Note - The information contained in this post is for general information purposes only. We try our level best to avoid any misinformation or abusive content. If you found any of such content on this website, please report us at [email protected]

Interested to publish an article at Law Corner? Click Here to submit your article.

Law Corner

4th Lex Research Hub National Research Paper Writing Competition, 2021

Publish your research paper and win exciting rewards including cash & part time work from home job offer!

Submit your research paper on any theme relating to law!

I Am Not interested
internship paid
lawsikho contract drafting