In January 1843, Daniel M’Naghten shot Edward Drummond, mistakenly believing he was the Prime Minister. Drummond died five days later, and M’Naghten was charged with murder. He pleaded not guilty due to insanity. At trial, medical experts and witnesses testified that M’Naghten was suffering from severe delusions that made him lose control over his actions. The court heard that while he might have seemed sane otherwise, his delusions led to the fatal shooting.
Issue before the Court
Can a person accused of an offence avoid criminal responsibility by claiming they were legally insane when the crime was committed?
Arguments of the Parties
The appellant (prosecution) argued that the defendant should be found guilty of murder because the insanity defense lacked credible evidence. They claimed the accused understood the nature and consequences of their actions, meeting the legal criteria for murder, and that using insanity as a defense was an unfounded attempt to evade punishment.
The respondent (defense) countered that the defendant was experiencing severe mental illness at the time of the murder, which impaired their ability to distinguish right from wrong or control their actions. They argued that under the law, a person cannot be held criminally liable if they were legally insane during the offense, and thus, the defendant should not be convicted.
Analysis of the Court
In this case, the jury found the defendant not guilty because they were legally insane at the time of the crime. The court explained that, generally, everyone is assumed to be mentally sound and able to understand the consequences of their actions. So, if someone wants to use the insanity defense, they must clearly prove that they had a serious mental disorder that affected their reasoning when the crime happened. Specifically, they would need to show that they either didn’t understand what they were doing or didn’t realize that what they were doing was wrong. This principle comes from what's known as the M’Naghten Rule. The rule serves as a guide for juries to decide if a person knew the difference between right and wrong when they committed the act. However, this rule isn’t applied in a vacuum it must be considered alongside how the defendant behaved and what the circumstances were in each individual case.
Concluding Remark
To sum up, the judges in the M’Naghten case (1843) laid down what we now call the M’Naghten Rules, which give us the legal test for insanity. According to these rules, if a defendant wants to argue that they were legally insane, they have to prove that they were suffering from a mental disorder that affected their ability to think clearly. Because of this mental condition, they either didn’t understand what they were actually doing, or if they did understand it, they didn’t realize that what they were doing was wrong.
