Insanity

• Full defence - not guilty by reason of insanity
• Burden of proof on defence who must prove def was suffering from insanity
• Rules of insanity set out by (M'Naghten)
• 1. Must be a defect of reason, defs reasoning powers must be impaired
• Must be more than absent-mindedness (Clarke)
• Can be permanent or temporary (Sullivan)
• 2. Caused by a disease of the mind (legal term)
• Can be temporary
• Sleep walking (Burgess)
• Hardening of arteries (Kemp)
• Epilepsy (Sullivan)
• Diabetes caused by internal factor due to not taking insulin (Hennessy)
• 3. Def must not know the nature of their act (Oye)
• If they did, they must not know it was legally wrong (Windle)
• If suffering from delusions but understood nature and quality of act then defence will fail (Johnson)
• If def voluntarily intoxicated, external factor and therefore defence will fail (Coley)