insanity defense

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Related to insanity plea: Temporary insanity

defense

 [de-fens´]
behavior directed to protection of the individual from injury.
character defense any character trait, e.g., a mannerism, attitude, or affectation, which serves as a defense mechanism.
insanity defense a legal concept that a person cannot be convicted of a crime if he lacked criminal responsibility by reason of insanity at the time of commission of the crime.
defense mechanism in psychology, an unconscious mental process or coping pattern that lessens the anxiety associated with a situation or internal conflict and protects the person from mental discomfort. In the theory of psychoanalysis, the ego, following the reality principle, conforms to the demands of the outside world, but the id (repressed unconscious), following the pleasure principle, pursues immediate gratification of desires and reduction of psychic tension. The superego (conscience or morality) may take either side. Defense mechanisms develop in order to control impulses or feelings that lead to inner conflicts, to reach compromises between conflicting impulses, and to reduce inner tensions. They help to manage or avoid anxiety, aggression, hostility, resentment, and frustration. Defense mechanisms are not pathological in themselves; they can be a means of dealing with unbearable situations. Among the most common defense mechanisms are denial, displacement, identification, projection, rationalization, reaction-formation, repression, and sublimation.
defense reaction a mental reaction that shuts out from consciousness ideas not acceptable to the ego. See also defense mechanism.

in·san·i·ty de·fense

in forensic psychiatry, the use in the courtroom of insanity as a mitigating factor in the defense of an accused on trial for a serious criminal offense. See: criminal insanity.

insanity defense

Forensic psychiatry A legal defense that a person cannot be convicted of a crime if he lacked criminal responsibility by reason of insanity–a term defined as a matter of law; the premise is that where there is no mens rea because of insanity, there is no criminal responsibility. See American Law Institute Formulation, Durham Rule, Irresistible impulse test, Long Island Rail Road massacre, M'Naughton Rule. Cf 'Black rage' defense, Television intoxication, 'Twinkie' defense.

insanity defense

In legal and forensic medicine, the premise that an insane person who commits a crime is not legally responsible for that act.
References in periodicals archive ?
Data from an eight-state study of cases involving insanity pleas are used to evaluate these effects.
accepting the insanity pleas," (23) this framework does not apply
In 2003, despite his insanity plea, he was convicted and sentenced to life in prison.
Years of research suggest "an enduring pattern of public animosity to the insanity plea.
In a nationwide poll taken a year before the attempted assassination by Hinckley, eighty-seven percent of the respondents agreed with the statement "too many murderers are using the insanity plea to keep from going to prison.
221) One study has shown that during the ten years after Hinckley's acquittal, less than one insanity plea was used for every 100 felony indictments, (222) Out of 586,063 felony indictments, only 5302 insanity pleas were entered.
Even without an insanity plea, the law required the judge to consider factors that might lessen the sentence.
This paper examines the insanity plea in practice in violent crime trials in England and Wales between 1832-1901, focussing on 145 women's trials and a comparative sample of ninety-three men's trials, in which the insanity acquittal figured.
For Marple and his backers, discrediting the insanity plea was necessary if the community was to accept the verdict.
Kirwin is at her best in describing the attempts by some defendants to fake insanity and the attempts by some defense lawyers to concoct a "designer defense" (Kirwin's apt term) to get their client off on an insanity plea.
22) A successful insanity plea acknowledges that the criminal act occurred, but the insanity defense holds that the accused is not criminally responsible due to his mental state.