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.
Murder is the unlawful killing of another human without justification or valid excuse committed with the necessary intention as defined by the law in a specific jurisdiction. This state of mind may, depending upon the jurisdiction, distinguish murder from other forms of unlawful homicide, such as manslaughter. Manslaughter is killing committed in the absence of malice, such as in the case of voluntary manslaughter brought about by reasonable provocation, or diminished capacity. Involuntary manslaughter, where it is recognized, is a killing that lacks all but the most attenuated guilty intent, recklessness.
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.
In criminal law, mens rea is the mental state of a defendant who is accused of committing a crime. In common law jurisdictions, most crimes require proof both of mens rea and actus reus before the defendant can be found guilty.
The gay panic defense or homosexual advance defense is a victim blaming strategy of legal defense, which refers to a situation in which a heterosexual individual charged with a violent crime against a homosexual individual claims they lost control and reacted violently because of an unwanted sexual advance that was made upon them. A defendant will use available legal defenses against assault and murder, with the aim of seeking an acquittal, a mitigated sentence, or a conviction of a lesser offense. A defendant may allege to have found the same-sex sexual advances so offensive or frightening that they were provoked into reacting, were acting in self-defense, were of diminished capacity, or were temporarily insane, and that this circumstance is exculpatory or mitigating.
A crime of passion, in popular usage, refers to a violent crime, especially homicide, in which the perpetrator commits the act against someone because of sudden strong impulse such as anger or jealousy rather than as a premeditated crime. A high level of social and legal acceptance of crimes of passion has been historically associated with France from the 19th century to the 1970s, and until recently with Latin America.
In criminal law, actus reus, Latin for "guilty act", is one of the elements normally required to prove commission of a crime in common law jurisdictions, the other being Latin: mens rea. In the United States, it is sometimes called the external element or the objective element of a crime.
In American jurisprudence, an excuse is a defense to criminal charges that is a distinct from an exculpation. Justification and excuse are different defenses in a criminal case. Exculpation is a related concept which reduces or extinguishes a person's culpability, such as their liability to pay compensation to the victim of a tort in the civil law.
In law, provocation is when a person is considered to have committed a criminal act partly because of a preceding set of events that might cause a reasonable individual to lose self control. This makes them less morally culpable than if the act was premeditated (pre-planned) and done out of pure malice. It "affects the quality of the actor's state of mind as an indicator of moral blameworthiness."
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.
Forensic psychiatry is a subspeciality of psychiatry and is related to criminology. It encompasses the interface between law and psychiatry. According to the American Academy of Psychiatry and the Law, it is defined as "a subspecialty of psychiatry in which scientific and clinical expertise is applied in legal contexts involving civil, criminal, correctional, regulatory, or legislative matters, and in specialized clinical consultations in areas such as risk assessment or employment." A forensic psychiatrist provides services – such as determination of competency to stand trial – to a court of law to facilitate the adjudicative process and provide treatment, such as medications and psychotherapy, to criminals.
Articles related to criminology and law enforcement.
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.
Settled insanity is defined as a permanent or "settled" condition caused by long-term substance abuse and differs from the temporary state of intoxication. In some United States jurisdictions, "settled insanity" can be used as a basis for an insanity defense, even though voluntary intoxication cannot, if the "settled insanity" negates one of the required elements of the crime such as malice aforethought. However, U.S. federal and state courts have differed in their interpretations of when the use of "settled insanity" is acceptable as an insanity defense and also over what is included in the concept of "settled insanity".
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 criminal law of the United States is a manifold system of laws and practices that connects crimes and consequences. In comparison, civil law addresses non-criminal disputes. The system varies considerably by jurisdiction, but conforms to the US Constitution. Generally there are two systems of criminal law to which a person maybe subject; the most frequent is state criminal law, and the other is federal law.
People v Schmidt, 216 N.Y. 324 (1915), is a criminal case interpreting "wrong" in the M'Naghten rule for an insanity defense.
The Royal Commission on Capital Punishment 1949–1953 reviewed the application of death penalty in the United Kingdom, including the questions of what crimes should receive the death penalty and what method of execution should be employed. The commission was set up by the Attlee government in an attempt to defuse the long-term political debate over capital punishment. The Royal Warrant establishing the commission instructed their inquiry to assume the retention of the death penalty. In their report, the Commission described their own task as "trying to find some practical half-way house between the present scope of the death penalty and its abolition"
Kahler v. Kansas, 589 U.S. ___ (2020), is a case of the United States Supreme Court in which the justices ruled that the Eighth and Fourteenth Amendments of the United States Constitution do not require that states adopt the insanity defense in criminal cases that are based on the defendant's ability to recognize right from wrong. It was argued on October 7, 2019 and decided on March 23, 2020.
