The insanity defense, also known as the mental disorder defense, is an affirmative defense by excuse in a criminal case, arguing that the defendant is not responsible for their actions due to a psychiatric disease at the time of the criminal act. This is contrasted with an excuse of provocation, in which the defendant is responsible, but the responsibility is lessened due to a temporary mental state. It is also contrasted with the justification of self defense or with the mitigation of imperfect self-defense. The insanity defense is also contrasted with a finding that a defendant cannot stand trial in a criminal case because a mental disease prevents them from effectively assisting counsel, from a civil finding in trusts and estates where a will is nullified because it was made when a mental disorder prevented a testator from recognizing the natural objects of their bounty, and from involuntary civil commitment to a mental institution, when anyone is found to be gravely disabled or to be a danger to themself or to others.
The M'Naghten rule(s) (pronounced, and sometimes spelled, McNaughton) is a legal test defining the defence of insanity that was formulated by the House of Lords in 1843. It is the established standard in UK criminal law. Versions have been adopted in some US states, currently or formerly, and other jurisdictions, either as case law or by statute. Its original wording is a proposed jury instruction:
that every man is to be presumed to be sane, and ... that to establish a defence on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was labouring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or if he did know it, that he did not know he was doing what was wrong.
Jury nullification, also known in the United Kingdom as jury equity, or a perverse verdict, is when the jury in a criminal trial gives a verdict of not guilty even though they think a defendant has broken the law. The jury's reasons may include the belief that the law itself is unjust, that the prosecutor has misapplied the law in the defendant's case, that the punishment for breaking the law is too harsh, or general frustrations with the criminal justice system. Some juries have also refused to convict due to their own prejudices in favor of the defendant. Such verdicts are possible because a jury has an absolute right to return any verdict it chooses. Nullification is not an official part of criminal procedure, but is the logical consequence of two rules governing the systems in which it exists:
- Jurors cannot be punished for passing an incorrect verdict.
- In many jurisdictions, a defendant who is acquitted cannot be tried a second time for the same offense.
In criminal law, diminished responsibility is a potential defense by excuse by which defendants argue that although they broke the law, they should not be held fully criminally liable for doing so, as their mental functions were "diminished" or impaired.
The trial of Louis Riel took place in Regina, Canada, in 1885. Louis Riel had been a leader of a resistance movement by the Métis and First Nations people of western Canada against the Government of Canada in what is now the province of Saskatchewan. Known as the North-West Rebellion, this resistance was suppressed by the Canadian military, which led to Riel's surrender and trial for treason. The trial, which took place in July 1885 and lasted five days, resulted in a guilty verdict. He was also given a choice to plead guilty or insanity. Riel was subsequently executed by hanging, an outcome which has had a lasting negative impact on relations between Anglophone Canadians and the Riel supporters among French Canadians.
Daniel M'Naghten was a Scottish woodturner who assassinated English civil servant Edward Drummond while suffering from paranoid delusions. Following his trial and its aftermath, his name has been given to the legal test of criminal insanity in England and other common law jurisdictions known as the M'Naghten rules.
Felo de se was a concept applied against the personal estates (assets) of adults who ended their own lives. Early English common law, among others, by this concept considered suicide a crime—a person found guilty of it, though dead, would ordinarily see penalties including forfeiture of property to the monarch and a shameful burial. Beginning in the seventeenth century precedent and coroners' custom gradually deemed suicide temporary insanity—court-pronounced conviction and penalty to heirs were gradually phased out.
In criminal law, automatism is a rarely used criminal defence. It is one of the mental condition defences that relate to the mental state of the defendant. Automatism can be seen variously as lack of voluntariness, lack of culpability (unconsciousness) or excuse. Automatism means that the defendant was not aware of his or her actions when making the particular movements that constituted the illegal act.
Edward Oxford was an English man who attempted to assassinate Queen Victoria in 1840. He was the first of seven unconnected people who tried to kill her between 1840 and 1882. Born and raised in Birmingham, he showed erratic behaviour which was sometimes threatening or violent. He had a series of jobs in pubs, all of which he lost because of his conduct. In 1840, shortly after being dismissed from yet another pub, he purchased two pistols and fired twice at Queen Victoria and her husband, Prince Albert. No-one was hurt.
Sir Nicolas Conyngham Tindal, PC was a celebrated English lawyer who successfully defended the then Queen of the United Kingdom, Caroline of Brunswick, at her trial for adultery in 1820. As Chief Justice of Common Pleas, an office he held with distinction from 1829 to 1846, he was responsible for the inception of the special verdict "Not Guilty by reason of insanity" at the trial of Daniel M'Naghten.
R v Parks, [1992] 2 S.C.R. 871 is a leading Supreme Court of Canada decision on the criminal automatism defence.
James Hadfield or Hatfield attempted to assassinate George III of Great Britain in 1800 but was acquitted of attempted murder by reason of insanity.
The Criminal Lunatics Act 1800 was an Act of the Parliament of Great Britain that required and established a set procedure for the indefinite detention of mentally ill offenders. It was passed through the House of Commons in direct reaction to the trial of James Hadfield, who attempted to assassinate King George III.
In the law of England and Wales, fitness to plead is the capacity of a defendant in criminal proceedings to comprehend the course of those proceedings. The concept of fitness to plead also applies in Scots and Irish law. Its United States equivalent is competence to stand trial.
English criminal law concerns offences, their prevention and the consequences, in England and Wales. Criminal conduct is considered to be a wrong against the whole of a community, rather than just the private individuals affected. The state, in addition to certain international organisations, has responsibility for crime prevention, for bringing the culprits to justice, and for dealing with convicted offenders. The police, the criminal courts and prisons are all publicly funded services, though the main focus of criminal law concerns the role of the courts, how they apply criminal statutes and common law, and why some forms of behaviour are considered criminal. The fundamentals of a crime are a guilty act and a guilty mental state. The traditional view is that moral culpability requires that a defendant should have recognised or intended that they were acting wrongly, although in modern regulation a large number of offences relating to road traffic, environmental damage, financial services and corporations, create strict liability that can be proven simply by the guilty act.
Scots criminal law relies far more heavily on common law than in England and Wales. Scottish criminal law includes offences against the person of murder, culpable homicide, rape and assault, offences against property such as theft and malicious mischief, and public order offences including mobbing and breach of the peace. Scottish criminal law can also be found in the statutes of the UK Parliament with some areas of criminal law, such as misuse of drugs and traffic offences appearing identical on both sides of the Border. Scottish criminal law can also be found in the statute books of the Scottish Parliament such as the Sexual Offences (Scotland) Act 2009 and Prostitution (Scotland) Act 2007 which only apply to Scotland. In fact, the Scots requirement of corroboration in criminal matters changes the practical prosecution of crimes derived from the same enactment. Corroboration is not required in England or in civil cases in Scotland. Scots law is one of the few legal systems that require corroboration.
Insanity in English law is a defence to criminal charges based on the idea that the defendant was unable to understand what he was doing, or, that he was unable to understand that what he was doing was wrong.
R v Burgess [1991] 2 QB 92 was an appeal in the Court of Appeal of England and Wales that adjudged sleepwalking entailing violence from an internal, organic cause amounts to insane automatism. At first instance Burgess was likewise found not guilty by reason of insanity as his case fell under the M'Naghten Rules. This would entail a possible stigma and a treatment plan. His defence team appealed arguing such automatism was no form of 'insanity' but fell within the class of automatism such as a spiked drink which could show a complete lack of mens rea, outside the realms of normal mental health, to make him guilty. The court ruled that violent sleepwalking with no external triggers was considered insane automatism. Thus the appeal was heard, argued, the law and its consequences judicially considered. The appeal was dismissed.
This disability rights timeline lists events outside the United States relating to the civil rights of people with disabilities, including court decisions, the passage of legislation, activists' actions, significant abuses of people with disabilities, and the founding of various organizations. Although the disability rights movement itself began in the 1960s, advocacy for the rights of people with disabilities started much earlier and continues to the present.
In Rex v Bourke, an important case in South African criminal law, the Transvaal Provincial Division (TPD) held that, under Roman-Dutch law, drunkenness is, as a general rule, no defence to a crime, although it may be a reason for mitigation of punishment. If the drunkenness is not voluntary—that is, if not caused by an act of the accused—and results in rendering the accused unconscious of what he was doing, he would not be responsible in law for an act done while in such a state. If constant drunkenness has induced a state of mental disease rendering the accused unconscious of his act at the time, he is not responsible and can be declared insane. Where a special intention is necessary to constitute a particular offence, drunkenness might reduce the crime from a more serious to a less serious one.
