The Criminal Jurisprudence applicable in India views the defence of insanity as an instrument towards proving the innocence of a person accused with an offence punishable under the Indian Penal Code 1860 or any other law for the time being in force. The concept based on the fact that if a person commits a crime while he is insane or suffering from the psychological disorder due to which fails to understand the consequences of his act/commission. However, in the legal arena, to prove insanity, mere sufferance of any mental disorder is not the sole determinant. The onus of proving insanity before the court rests solely on the person alleged of the crime, accompanied by evidence. The current article centers on the concept of the defense of insanity, which has proved to be a loophole in the contemporary judicial mechanism.


Where a person admits the wrong has been committed by him and pleads lack of understanding of the consequences such that he is barred from being punished for the same under the provisions of any of the laws for the time being in force in India, is termed as the defence that is available to him for his mental disorder.

Section 84 of the India Penal Code 1860 lay down provision regarding Acts of any individual

who is of an unsound mind. The section reads as follows-

"Nothing is an offence which is done by a person who, at the time of doing it, because of unsoundness of mind, is incapable of knowing the nature of the act, or that he is doing what is wrong or contrary to law."

The rationale behind enacting such a provision was that mental disorder or abnormality could be considered an exception while punishing a person guilty is based on the legal maxim actus non facitreum, nisi mens sit rea, i.e., an act which is forbidden by law if does not involves a guilty mind will not be punishable by the penal law. The unsoundness of mind acting as a complete defence can be justified by the contention that an insane person is incapable of forming a criminal intent; a mad person has no will, i.e., furiosisnullavoluntas; and he is like one who is not present or furiosisabsentis low est. Further, it is believed that a person suffering from mental abnormality is already punished for life by his madness (furiosisfurore sui puniter). The defence of insanity is also referred to as the Law of Insanity. It was held to be of great significance for it involved the understanding of the mental position of an individual and under certain circumstances, if not proven otherwise, as a means to grant relief from criminal charges.


The origin of the concept of insanity as a defence can be traced to the times of laws in Ancient Rome and Greece. The first instance of the defence was seen to be recorded in the English Legal Treaties of 1581, wherein a person, if kills another in the time of his lunacy, cannot be held accountable for the same. Post this the concept underwent huge developments and subsequently a "Wild Beast" test was brought to effect in the 18th Century whereby it was said that any person who commits an offense would not be charged in case he has the level of understanding of an infant or that of a wild beast. This laid the foundation on which stood the basis of the law of insanity and thus marked the advent of the insanity to be recognized as a defence in criminal proceedings. Subsequently, many other tests were deduced i.e., the Delusion Test, the Good and the Evil Test, etc. which laid down the basis for the landmark pronouncement of the English Court in R v. McNaughton often referred to as the McNaughton Test.

In the instant case, McNaughton killed one other named Edward Drummond mistaking him to be someone else. McNaughton was mentally disturbed and was not sane, was acquitted by the court of the charges of murder, and the jury gave directions for admission of McNaughton in a mental asylum. Post this, the House of the Lords sat for a discussion and laid a five-point proposition, which later constituted what is known as the McNaughton test. These included-

· There lies an assumption that a convict is sane until proven otherwise.

· In case the insane person is capable of forming an understanding of the act being done by him, he shall not be exempted from the charges and the punishment.

· To prove insanity, it is essential to show that the accused is incapable of understanding the consequences of his act.

· That the person is suffering from real delusions.

· It is the jury whose decision has finality and is binding as to whether a person is insane or sane.

These were used as precedents to decide further cases.


It is well established now that what the criminal law considers is legal insanity and not merely medical insanity. A person who is suffering merely from a mental abnormality is not said to be entitled to the defence of insanity under the criminal justice system. Legal insanity refers to the satisfaction of the criteria embodied in the provision of India Penal Code, u/s. 84. It is essential as to the accused to prove the requirements that are laid down in the said section. The courts, through various judicial pronouncements, have distinguished between legal and medical insanity. It has made it crystal clear that what courts/the justice system is concerned with is the legal insanity and not the latter. A simple mental illness for which a person undergoes medical treatment is referred to as Medical Insanity, however, in legal insanity, it is proved that not just is the person suffering from medical insanity but also lacks reasoning to know the act he is committing and the after-effects; it is referred to as the mental state of the offender at the time the criminal act was carried out.

In the case of Surendra Mishra v. the State of Jharkhand (2011) 11 SCC 495, the Apex Court held that no person who has mental illness is saved from the charges for what S. 84 of IPC exempts is Legal, not Medical insanity.

Also, the Hon'ble Apex Court in Gajraj Singh v. State of Rajasthan Appeal (Crl.) 1313 of 2006 held no protection under the provision of IPC can be given to an accused merely on the ground that he is suffering from irresistible impulse; or delusion of partial nature; or mental abnormality.


Various reasons are leading to the shortfalls of the defence of insanity, such as-

· The defence is often seen to be misused to escape from punishment. As already stated, that it is tough to establish sanity or insanity as it was when the act was done, the defence is purely subject to the prudence of the Judge. Thus the law of insanity loses its essence.

· In the current times, the massive misuse of the provision has led to the abolition of the same in several countries. However, the same still finds a place in India, and people often see that, even after committing brutal crimes, accused get released and acquitted on the ground of insanity. Thus jeopardizing the moral fabric of the society.

· The practice is that it is on the accused to prove and avail the defence. The law does not accept medical insanity but legal insanity. It is often the case that a genuine person suffering from insanity is unable to prove legal insanity as per the requirements of S.84 of IPC and thus faces severe legal consequences.


In Current times, the Insanity defence has become a menace to the Criminal Justice System. It acts as a weapon in the hands of the criminals to escape law even after committing serious crimes. It is also difficult to prove the sanity and state of mind of people when the offence was committed. However, the blame is to also fall on the redundancy of the legal jurisprudence of the Country, which works as a fuel to the fire diminishing the very essence of the defence to a mere game of words.

The insanity defence has merely crumbled to a tool for evading legal charges and consequences. To overcome the lacunae, it is essential to distinguish between violent offenders and insane offenders through straightforward enactments, and stricter reforms in this matter are indispensable.


Shreya Srivastava

Amity Law School, Kolkata

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