Insanity (at the time of the alleged offence) Flashcards
(7 cards)
Criteria
M’Naghten’s Case: “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”
Defect of reason
ability to reason must be impaired
R v Clarke: depression and absent-mindedness not a sufficient defect of reason
Disease of the mind
(not a medical definition!)
R v Kemp: disease of the mind is any “internal” condition affecting the brain, regardless of whether it is temporary or controllable (e.g. build-up of arteriosclerosis)
D did not know the nature or quality of the act
Stephen: gives example of someone cutting off the head of someone who was asleep because it would be great fun to see him looking for it when he woke up
D did not know the act was wrong
R v Keal: D must establish both that he did not know the act was unlawful and that he did not know the act was morally wrong (i.e. to be liable, D must believe the act was both legally and morally right)
Examples of valid diseases of the mind/internal causes
R v Burgess: sleepwalking
R v Sullivan: epilepsy
R v Hennessy: hyperglycaemia (diabetes as internal cause)
- Contrast to R v Quick: hypoglycaemia, sane automatism, insulin as external cause
Theory
Morris: study where cohort of mentally disordered people with a range of mental illnesses had no greater incidence of criminal offending than a same-sized cohort of people randomly selected from the community
Gunn and Taylor: risk of being killed by a mentally insane person is ‘small’, risk that a mentally ill person will commit suicide is about 100 times greater- is our society more concerned with protecting the lives of the sane rather than insane?
Moore: justifies the defence; the criminal law is addressed to those who are rational and have capacity to comply with its rules- a mentally ill person lacks such capacity and is exempt from its requirements
