What Is the M’Naghten Rule For Insanity Defense?

The M’Naghten Rule tests whether defendants knew their act’s nature or wrongfulness when claiming insanity. This article covers its history, examples, criticism, and other insanity defense standards courts may apply.

By Brad Nakase, Attorney

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Table of Contents

1. Introduction

2. Court Assessments for the Defense of Insanity

3. An Overview and History of the M’Naghten Rule

4. Criminal Insanity & Daniel M’Naghten

5. The Rule of M’Naghten

6. M’Naghten Rule: Examples of Insanity

7. The M’Naghten Rule’s Criticism

8. Additional Tests for Insanity Defense

9. Consult an Attorney to Find Out More About the M’Naghten Rule

Introduction

The M’Naghten Rule is a legal standard. Courts utilize it to determine the mental state of criminal defendants. It is one of the insanity defense’s various tests. However, some people think that this rule produces erroneous results.

When representing an individual in a criminal case, attorneys may employ a variety of defense tactics. However, the insanity defense is difficult to apply, despite how it is portrayed in films and television. For a court to hold a criminal defendant not guilty due to insanity, it must satisfy the jurisdiction’s standard of legal insanity.

The M’Naghten Rule for judging legal insanity is the main topic of this article. Legal counsel can assist a defendant in receiving fair consideration if their mental ability is in doubt. You can see a criminal law lawyer if you need assistance with defense tactics.

Court Assessments for the Defense of Insanity

One of the following criteria or tests will be used by courts to define legal insanity:

The Test of the Model Penal Code
The Durham Regulation
The Test of Irresistible Impulse
The Rule of M’Naghten

The court does not have the authority to choose which test to use. Rather, it is determined by the rules of a specific state.

An Overview and History of the M’Naghten Rule

An English case from the middle of the 19th century gave rise to the M’Naghten Rule. There, an individual claimed he was not accountable for his unlawful deed because of a mental illness. Continue reading to discover more about the M’Naghten case and how the M’Naghten Rule came to be in criminal law.

Criminal Insanity & Daniel M’Naghten

A British guy named Daniel M’Naghten had a mental disorder. It led to paranoid delusions. He believed that the Tories & Catholic priests were plotting against him. According to the evidence presented during his criminal prosecution, he thought spies were following him and planned to murder him.

M’Naghten intended to assassinate Sir Robert Peel, the Tory PM, in an attempt to put an end to the purported persecution. He pursued an individual who had left Peel’s home in 1843. M’Naghten mistook the man for Peel. Actually, it was Edward Drummond, Peel’s secretary. Drummond was shot and killed by M’Naghten.

M’Naghten was taken into custody by the police and charged with murder. During the trial, M’Naghten’s lawyer raised the defense of insanity. According to expert testimony, M’Naghten’s mental health at the point of the crime was damaged by his delusional notions. His lawyer contended that M’Naghten was unable to discriminate between good and bad when he killed Drummond.

M’Naghten was acquitted when the jury found him to be insane. For the remainder of his life, M’Naghten was institutionalized by the Crown.

The Rule of M’Naghten

The jury’s decision was disapproved of by the Queen of England. She requested that the English House of Lords debate and consider defenses for insanity. The M’Naghten Rule was the result of these conversations. It is helpful to first learn what the M’Naghten rule is.

The following are the main topics of this test:

Whether an accused criminal was aware of the essence of the offense
Whether they knew what was good and wrong when they performed the crime

Therefore, for a court to pronounce a defendant legally insane, it must satisfy one of those two unique requirements.

The M’Naghten test was adopted by US courts. Courts may disagree when using this test over whether the wrong pertains to a legal wrong, a moral wrong, or both. Furthermore, some states no longer consider a person to be legally insane if they don’t completely comprehend what they’ve done.

Also Read: What Is a Second-Degree Murder?

M’Naghten Rule: Examples of Insanity

Seeing a few instances of how courts might apply the rule in specific situations is the best approach to comprehend what the M’Naghten rule is.

Example 1: After killing his family, the man quietly awaited the arrival of the police. There were testimonies of three mental health specialists. He was too mentally sick to recognize the wrongness of his crimes. He was given a 10-year term in a mental health facility. A jury declared him not culpable.

Example 2: A woman had severe schizophrenia. She attacked her neighbor. She was accused of assault and battery by the authorities. In reality, she said, her neighbor was a devil attempting to steal her soul. Because she was unable to comprehend the nature of her conduct, a jury ruled her not at fault by reason of insanity.

The two ways a judge may pronounce an accused person legally insane using this rule are demonstrated by the aforementioned examples.

The M’Naghten Rule’s Criticism

The M’Naghten test for legal mental illness has encountered a number of difficulties. Some detractors contend that defendants who satisfy the legal standard of insanity may not necessarily satisfy the medical requirements. In spite of this, courts frequently impose required medical care on them. Much of this debate revolves around what the M’Naghten rule is & its repercussions.

The M’Naghten Rule, according to some critics, does not differentiate between defendants who pose a public threat and those who don’t. Furthermore, others contend that it fails to distinguish between transient mental disorders and chronic illnesses.

Lastly, some contend that the law makes it too simple for a defendant with a serious mental illness to avoid accountability for any offenses.

Additional Tests for Insanity Defense

To decide whether a person with a mental illness is eligible for the insanity defense, courts have used additional legal standards.

A court in New Hampshire rejected the M’Naghten Rule in 1871. In that case, the court decided that if a person’s crime was caused by their mental illness, they are not guilty. In other words, “but for” their mental disorder, the defendant wouldn’t have executed the crime.

The Irresistible Impulse Test was developed by the Alabama Supreme Court in 1887. The court observed that the defendant was unable to stop himself from committing a crime. They were aware that what they were doing was illegal, though. A defendant has to demonstrate that they have a mental disorder. It prevented them from exercising self-control.

The Durham vs. United States case established the Durham Statute. It was decided by the US Court of Appeals (District of Columbia) in 1954. According to the court, “an accused isn’t legally accountable if his illegal conduct was the outcome of a mental disorder or mental defect.”

The Durham Rule was overturned by the same Court of Appeals in 1972. The American Law Institute’s Model Penal Code (MPC) took its place. The following is the MPC’s rule:

“A person is not accountable for illegal behavior if, due to a mental illness or defect, at the time of the behavior, he lacks sufficient capacity to comprehend the criminality [unlawfulness] of his action or to adjust his behavior to the rules of law.”

The MPC’s ruling is currently applied in all federal circuits and the majority of states.

Consult an Attorney to Find Out More About the M’Naghten Rule

The insanity argument has certain requirements for eligibility and can have long-term repercussions. The issue becomes clearer once you know what the M’Naghten rule is. Speaking with an experienced lawyer should be your first course of action if you are subject to criminal accusations and would like to learn more about the requirements of an insanity defense. Learn more and get in touch with a nearby criminal defense lawyer right now.