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.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

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.
Farlex Partner Medical Dictionary © Farlex 2012

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.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

insanity defense

In legal and forensic medicine, the premise that an insane person who commits a crime is not legally responsible for that act.
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
The widespread public distrust of the insanity defense has been
In announcing his involuntary intoxication defense, Haywood said he provided notice that complied with standards for an insanity defense.
As courts have divided on how to treat the question of noncompliance-induced insanity, the question becomes what approach best comports with the purposes of the insanity defense. Doctrinally, insanity concentrates on the defendant's mental state at the time the crime was committed.
To understand the history of the insanity defense it is paramount
(11) Between the five experts there was only one instance where the defense used the insanity defense despite the RCM 706 board determining the subject was mentally responsible, and only two instances where the government took a case to trial where the sanity board found that the subject was not mentally responsible.
For example, the Insanity Defense Attitude-Revised (IDA-R) was developed to evaluate overall attitudes toward the defense.
The Insanity Defense Reform Project was an eight-state study of insanity defense reforms before and after the Hinckley decision; those states were California, Georgia, Montana, New Jersey, New York, Ohio, Washington, and Wisconsin.
Once again, the insanity defense came under scrutiny as a result of the Andrea Yates verdict.
In Norway, an insanity defense requires that a defendant be in a state of psychosis while committing the crime with which he or she is charged.
Wimberly's attorney used an insanity defense, arguing that she had suffered years of physical, sexual and emotional abuse ...