Insanity

• M'Naughten 


  key case for insanity which follows the M'Naughten rules
• 1. R v Clarke


  The defect of reason must be more than absent-mindedness or confusion. D must be deprived of the power of reasoning
• 2. R v Kemp


  Insanity must be due to a physical disease (Internal) which can be temporary or permanent
• 2. R v Quick


  D was not insane as the defect was due to an external factor, the insulin
• 2. R v Sullivan


  epilepsy is a disease of the mind which cause a defect of reason
• 2. R v Burgess


  Sleepwalking is an internal factor
• 3. R v Bratty v AG ref for Northern Ireland


  not guilty by reason of insanity as the epilepsy may have prevented D knowing the nature of his act
• 4. R v Windle


  words can demonstrate D knows he is doing something wrong
• 4. R v Johnson


  There is no need for a judge to put the defence of insanity before a jury if D knew what they did was legally wrong
• 4. R v Elmi


  Insane if D believed what he did was not legally or morally wrong
• 5. R v Lipman


  Voluntarily taking drugs or alcohol will exclude the defence of insanity