Legal Standards for the Defence of Insanity

Author: Teesha Gupta is a third-year law student at Institute of Law, Nirma University.

An odd character frequently appears on stage in the criminal justice theater where guilt and innocence clash: insanity. The defence of insanity entices us into the maze of the human mind with its elusiveness and the puzzling dance between mental health and guilt. The defence of insanity in criminal law is a fascinating topic, and in this research paper, we aim to unravel its intricacies, put its presumptions to the test, and navigate the perilous terrain of legal and psychological discourse.

Decoding The M’ Naghten Rule

The defence of Insanity originated in England in 1843 following the case of Daniel M’ Naghten marking the birth of this legal concept wherein, M’ Naghten attempted to assassinate the British Prime Minister, believing that the head of the government was conspiring against him. Due to his psychosis, M’Naghten was acquitted by the court establishing the M’ Naghten rule, which is the first test used to determine criminal liability in cases. The rule suggests that, if any person is found to have a mental disorder at the time of commission of the offence that is so grave to –

Interfere with the ability of the person to know the consequence of the illegal act, or
Interfere with the ability of the person to know that the said act is wrong itself.

Both the United States of America and the United Kingdom have adopted this as the standard test for insanity in criminal cases.

Relevance of The Irresistible Impulse Test

This rule was the response to the criticisms of the M’ Naghten Rule when some legal experts started proposing a broader interpretation of insanity, going beyond just the cognitive aspect of the M’Naghten definition. This expanded test would consider not only whether defendants understand right from wrong but also whether they have the ability to control their urges to engage in wrongful behavior. This test proposes that if a person commits a crime but couldn’t resist their actions, even though they knew those actions were wrong, they should not be held accountable or liable for their actions.

This test came into the limelight after the landmark case of Parsons v. State, the Alabama court concluded that despite the defendant’s ability to differentiate between right and wrong, he was still subject to “duress of such mental disease [that] he had … lost the power to choose between right and wrong” and that “his free agency was at the time destroyed,” and thus, “the alleged crime was so connected with such mental disease, in the relation of cause and effect, as to have been the product of it solely.” By making this determination, the court attributed the responsibility for the crime to the defendant’s mental illness, even though the defendant had the capacity to differentiate between right and wrong. As a result, the court found the defendant not guilty by reason of insanity.

Durham Rule

The Dhuram Rule was originally adopted in New Hampshire in 1971 in the eminent of Durham v. United Case. Though originally meant to simplify the infamous M’ Naghton Rule,Dhuram rule, is sometimes also referred to as the “product test,” it proposes that the perpetrator shall not attract criminal liability in case “his unlawful act is the product of a mental disease of defect.” Paradoxically, the said rule was very difficult to apply on ground, thus, was heavily criticized.Presently, New Hampshire is the sole user of this rule to define Insanity.

Substantial Capacity Test

The substantial capacity test which is laid in the Model Penal Code is as follows: “A person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect he lacks substantial capacity either to appreciate the criminality [wrongfulness] of his conduct or to confirm his conduct to the requirements of law.”

This test has commonality with the M’ Naughten Rule and the irresistible impulse test as they both require the presence of a mental illness or defect. Also, it necessitates volitional and cognitive capacity of the accused. But it is far easier to establish insanity under the Substantial Capacity test as the cognitive and volitional demands are lowered to more lenient thresholds. Moreover, the word “appreciate” carries an emotional component, character or personality evidence pertaining to the defendant is pertinent and most likely admissible to support the defense.

The Indian Context

According to Section 84 of the Indian Penal Code, 1860 – Nothing is an offence which is done by a person who, at the time of doing 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.

Insanity defence under this section, is only available when these two conditions are met –

The presence of mental unsoundness during the commission of the offense, commonly referred to as “medical insanity.”
As a result of the mental unsoundness, the person was unable to comprehend the nature of the act or recognize that it was either morally wrong or against the law, which is referred to as “legal insanity.”

Under the second aspect, the defendant must demonstrate one of the following incapacities:

1. They were unaware of the nature of the act (cognitive incapacity).

2. Even if they were aware of the nature of the act, they did not recognize it as morally wrong.

3. Even if they were aware of the nature of the act, they did not realize it was contrary to the law.

Once medical insanity has been established, courts consider the “totality of circumstances” to assess “legal insanity” and determine if the requirements for a successful defense have been met. However, courts rarely conduct an active examination of legal insanity. Instead, they often infer legal insanity based on various factors, including the nature of the mental illness, the absence of motive, and the behavior of the accused before, during, and after the act.

Moral Basis of The Defence

It is critical to consider a range of ethical viewpoints and participate in ongoing ethical discussions while considering the moral foundations of the insanity defense. Justice, personal accountability, and the ethical treatment of people with mental illness within the criminal justice system are all issues that are closely related to the moral and intellectual underpinnings of the insanity defense. The foundations of the insanity defense can be understood by turning to various moral theories, such as utilitarianism, virtue ethics, and Kantian ethics.

Utilitarians may contend that the insanity defense protects both society and the offender by averting harm. Society can make more informed decisions that decrease the likelihood of future harm by taking a defendant’s mental state into account. Therefore, from a utilitarian perspective, there might be a moral requirement to consider mental condition when judging guilt.

Discussions about virtue ethics, which emphasize the growth of moral character, can also be helpful. It implies that a just society ought to embody virtues like empathy and compassion. Virtue ethics may encourage society and the legal system to act with compassion by giving treatment and rehabilitation a higher priority than punishment when it comes to those with severe mental illnesses. This is consistent with the notion that a morally upright society takes care of its most defenseless citizens.

It is clear that these philosophical viewpoints offer various vantage points of investigation into the question of whether society has a moral obligation to take a defendant’s mental condition into account when judging guilt and punishment. The moral obligation to uphold people’s dignity may be emphasized by Kantian ethics, the necessity to minimize harm to society may be emphasized by utilitarianism, and the value of compassion and caring for the weak may be emphasized by virtue ethics. These viewpoints jointly shape the insanity defense’s philosophical foundations and practical use within the legal system, contributing to the ongoing moral discussion surrounding it.