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 is any variant of the 1840s jury instruction in a criminal case when there is a defence of insanity:
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.
Actus reus, sometimes called the external element or the objective element of a crime, is the Latin term for the "guilty act", which, when proving it before the court beyond a reasonable doubt in combination with the mens rea, "guilty mind", produces criminal liability in the common law-based criminal law jurisdictions of England and Wales, Canada, Australia, India, Kenya, Pakistan, South Africa, New Zealand, Scotland, Nigeria, Ghana, Ireland, Israel and the United States. In the United States, some crimes also require proof of an attendant circumstance.
Sleepwalking, also known as somnambulism or noctambulism, is a phenomenon of combined sleep and wakefulness. It is classified as a sleep disorder belonging to the parasomnia family. It occurs during slow wave stage of sleep, in a state of low consciousness, with performance of activities that are usually performed during a state of full consciousness. These activities can be as benign as talking, sitting up in bed, walking to a bathroom, consuming food, and cleaning, or as hazardous as cooking, driving a motor vehicle, violent gestures and grabbing at hallucinated objects.
Dorothy Otnow Lewis is an American psychiatrist and author who has been an expert witness at a number of high-profile cases.
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.
Automatic behavior is the spontaneous production of purposeless verbal or motor behavior without conscious self-control or self-censorship. This condition can be observed in a variety of contexts, including schizophrenia, psychogenic fugue, epilepsy, narcolepsy, or in response to a traumatic event.
R v Daviault [1994] 3 S.C.R. 63, is a Supreme Court of Canada decision on the availability of the defence of intoxication for "general intent" criminal offences. The Leary rule which eliminated the defence was found unconstitutional in violation of both section 7 and 11(d) of the Canadian Charter of Rights and Freedoms. Instead, intoxication can only be used as a defence where it is so extreme that it is akin to automatism or insanity.
R v Parks, [1992] 2 S.C.R. 871 is a leading Supreme Court of Canada decision on the criminal automatism defence.
R v Stone, [1999] 2 S.C.R. 290 is a leading Supreme Court of Canada decision on the use of the defence of automatism in a criminal trial.
R v Swain, [1991] 1 S.C.R. 933 is a leading constitutional decision of the Supreme Court of Canada on certain rights of the mentally ill in their criminal defence. The case concerned a constitutional challenge of the common law rule permitting the Crown to adduce evidence of an accused's insanity and section 542(2) of the Criminal Code, which allowed for the indeterminate detention of an accused who is found not guilty by reason of "insanity". The Court held that both the common law rule and the Code provision were unconstitutional. As a result, the Court created a new common law rule that was constitutional, and Parliament created new laws of what to do with individuals who were found not criminally responsible by reason of a mental disorder. The parties to the case were the appellant, Swain, the respondent, the Crown, and the following interveners: the Attorney General of Canada, the Lieutenant Governor's Board of Review of Ontario, the Canadian Disability Rights Council, the Canadian Mental Health Association, and the Canadian Association for Community Living.
Bratty v Attorney-General for Northern Ireland [1963] AC 386, [1961] 3 All ER 523, [1961] UKHL 3 is a House of Lords decision relating to non-insane automatism. The court decided that medical evidence is needed to prove that the defendant was not aware of what they were doing, and if this is available, the burden of proof lies with the prosecution to prove that intention was present.
R v Quick [1973] QB 910 is an English criminal case, as to sane automatism and the sub-category of self-inducement of such a state. The court ruled that it may not be used as a defence if the defendant's loss of self-control was on the part of negligence in consuming or not consuming something which someone ought to but the jury must be properly directed so as to make all relevant findings of fact. The ruling stresses that automatism is usually easily distinct from insanity, in the few cases where the lines are blurred it is a complex problem for prosecutors and mental health professionals.
R v Bailey is a 1983 decision of the Court of Appeal of England and Wales considering criminal responsibility as to non-insane automatism. The broad questions addressed were whether a hampered state of mind, which the accused may have a legal and moral duty to lessen or avoid, gave him a legal excuse for his actions; and whether as to any incapacity there was strong countering evidence on the facts involved. The court ruled that the jury had been misdirected as to the effect of a defendant's mental state on his criminal liability. However, Bailey's defence had not been supported by sufficient evidence to support an acquittal and his appeal was dismissed.
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.
In the field of criminal law, there are a variety of conditions that will tend to negate elements of a crime, known as defenses. The label may be apt in jurisdictions where the accused may be assigned some burden before a tribunal. However, in many jurisdictions, the entire burden to prove a crime is on the prosecution, which also must prove the absence of these defenses, where implicated. In other words, in many jurisdictions the absence of these so-called defenses is treated as an element of the crime. So-called defenses may provide partial or total refuge from punishment.
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.
The Trial of Lunatics Act 1883 is an Act of the Parliament of the United Kingdom, allowing the jury to return a verdict that the defendant was guilty, but insane at the time, and should be kept in custody as a "criminal lunatic". This Act was passed at the request of Queen Victoria, who, the target of frequent attacks by mentally ill individuals, demanded that the verdict be changed from "not guilty" so as to act as a deterrent to other lunatics; the phrasing of "guilty of the act or omission charged, but insane so as not to be responsible, according to law, for his actions" remained in use until the Criminal Procedure (Insanity) Act 1964.
South African criminal law is the body of national law relating to crime in South Africa. In the definition of Van der Walt et al., a crime is "conduct which common or statute law prohibits and expressly or impliedly subjects to punishment remissible by the state alone and which the offender cannot avoid by his own act once he has been convicted." Crime involves the infliction of harm against society. The function or object of criminal law is to provide a social mechanism with which to coerce members of society to abstain from conduct that is harmful to the interests of society.
King v. Cogdon (1950) is a criminal case heard by the Supreme Court of Victoria in Australia where a woman successfully defended herself against a homicide charge using the defence of (non-insane) automatism. The case was not formally reported but the case has been referenced both by legal scholars and those in other disciplines.
