M'Naughten test

M'Naughten test

Forensic psychiatry The most popular test for defining a person as insane under the law, which will find a defendant insane if she had a diseased mind that caused a defect of reason, such that when she acted, she either didn't know the act was wrong or didn't understand the nature and quality of her actions. See Insanity defense. Cf Durham rule, Irresistible impulse test, Substantial capacity test.
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735 (2006), in which the Supreme Court upheld the constitutionality of an Arizona statute that removed the cognitive incapacity element or second prong of the M'Naughten test.
The M'Naughten test restricts psychiatric testimony to the narrow scope of a defendant's cognitive capacity and frequently makes it impossible for expert witnesses to describe the complete picture of the defendant's mental illness (TCPOMIa).
As previously stated, the M'Naughten test restricts psychiatric testimony to the narrow scope of a defendant's cognitive capacity and can prevent the complete picture of the defendant's mental illness and state--so crucial in the Yates' case.