Insanity

• mcnaughten rules 


  1. Suffering defect of reason

  2. Caused by disease of the mind

  3. Didn't know nature and quality of act

  4. Didn't know what they were doing was wrong
• main case

  Mcnaughten- extreme paranoia, tried to kill sit robert peel presumption that every man is sane, prove on balance of probability
• defect of reason ≠ absentmindedness 


  R v Clarke
• disease of mind

  must cause defect of reason, affect the brain, affect faculities of reason memory and understanding
• 'properly affects functions of mind'


  R v Hennessy
• 
  

  internal condition (arteries) affecting mind 


  R v kemp
• 'sleep is normal, sleepwalking resulting in violence is not'


  Lord Lane CJ in R v Burgess
• organic insanity 


  brain has been damaged by a physical or degenerative cause (e.g. epilepsy)
• functional sanity

  No organic reason for the damage to the brain
• insanity diabetes

  R v Hennessy- drove while disqualified, hadn't taken insulin and reaction worsened by emotional state
• voluntary intoxication

  R v Coley - played a violent video game, took cannabis, threatened neighbours with knife
• didn't know nature or quality of act 


  R v Oye -believed police officers had demonic faces
• didn't know what he was doing was wrong 


  R v Johnson - stabbed a neighbour during paranoid schizophrenia episode, knew what he was doing = no defence
• needs not be permanent, can be transient or intermittent

  R v Sullivan