Mental Capacity Defences

• Define Automatism

  Defined in [Bratty] as 'an act done by the muscles without the control of the mind; or an act done by a person who is not conscious of what he is doing'
• Automatism may be a defence to

  all crimes, including those classed as strict liability offences
• 3 things required for automatism to be successful

  A total loss of voluntary control

  Caused by an external factor

  It is not self induced
• Total loss of voluntary control

  D must show that there was a complete loss of voluntary control to rely on automatism as per [Broome V Perkins]
• External Factor

  Difference between insanity and automatism = total loss of control must be from an external factor [Hill V Baxter]

  EG: blow to the head causing concussion, stung by a bee, PTSD [Quick] and [Lowe]
• Self-induced automatism

  If it was voluntary (drugs and alcohol) D is not able to use this defence and will be subject to the rules of intoxication as per [Lipman]

  If D's automatism is caused by something other than drugs/alcohol then may be able to use the defence but depends if they knew the risk of getting into such a condition [Bailey]
• Define Insanity

  Defence based on the idea that the D was unable to understand what he was doing or did not know his actions were unlawful
• Rules of Insanity as per [M'Naughten]

  Suffering from a defect of reason

  Caused by a disease of mind

  D did not know nature and quality of the act or that he did not know what he was doing was legally wrong
• Defect of reason

  D must show that he was suffering from a defect of reason (his ability to reason was impaired) [Clarke]
• Disease of the mind

  A legal term not a medical one

  Can be a mental or physical disease [Kemp]

  Diabetics [Hennesy] and sleepwalkers [Burgess] can use the defence of insanity
• D did not know nature/quality of the act was wrong

  Eg: if the D thinks he is cutting a loaf of bread but he is actually cutting the V's throat [Windle] and [Johnson]
• Effect

  When D is successfully proven of defence the jury must return a verdict of 'not guilty by reason of insanity' the judge can impose a hospital order, suspension order, or an absolute discharge
• Intoxication is defined as...

  having physical or mental control diminished by the effects of alcohol or drugs
• If despite their intoxicated state the D is still able to form the mens rea, then the defence will not apply as per [Kingston]
• Involuntary intoxication is 


  a defence to basic and specific intent crimes as long as no mens rea is formed
• 3 things regarding involuntary intoxication

  D has been spiked - normally results in a full acquittal [Allen]

  D has taken prescription drugs - leads to a full acquittal unless there is evidence of D being reckless [Bailey]

  D has an unexpected reaction to soporific drugs [Hardie]
• Voluntarily Intoxicated

  D has voluntarily consumed alc/drugs known to make people aggressive/out of control

  D will have a defence to specific but not basic intent crimes if they are incapable of forming mens rea [Beard] and [Majewski]
• Dutch Courage

  was established in [Gallagher] and is not a defence to any crime.