insanity defense

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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 ?
These two are the negation of the mens rea required by the definition of the offense, usually improperly called diminished capacity, and the insanity defense.
As a net result, the insanity defense is now limited to a relatively small number of extreme cases.
Intermittently, federal and state legislators introduce bills to eliminate the insanity defense based upon its putatively pernicious effect on notions of individual responsibility and (equally putative) overuse.
As with the insanity defense, defenders of psychiatry tend to minimize both the frequency of civil commitment and the importance of the psychiatrist's role in it.
The author's discussion about the American Law Institute (ALI) test of criminal responsibility is useful in understanding the insanity defense.
It's interesting, then, that none of the celebrated objective brain-analyzing technologies--not functional magnetic resonance imaging (fMRI), not positron emission tomography (PET), not computed axial tomography (CAT)--had any bearing on the Yates case as it was presented in court, or on insanity defense cases in general.
abnormal causation--justifies the insanity defense and explains its
The secular insanity defense was an outcome of this psychological revolution that grew out of Counter-Reformation struggles over the bodies of the mad and possessed.
Understanding the elements of the insanity defense therefore requires practitioners to have a basic understanding of its history.
7) The meaning of the insanity defense resides, he argued, not in abstract doctrinal formulations but in the concrete sensibilities of those who apply them.
Demonic possession, the belief that evil has pervaded the body, offers the investigator opportunities to develop themes of complicity between the evil forces and the suspect; however, demonic possession may create grounds for an insanity defense for the suspect.