Defences: Insanity

• Criminal Defences:

  • Here the defendant is not claiming they are innocent - they accept they did the crime, but put forward a "defence" as reason why they should escape punishment.
  • Can be separated into two types of defences:

  1. Mental Capacity Defences
  2. General Defences
• Mental Capacity Defences:

  • The defendant did not have he mental capacity to fulfil the mens rea of the offence.
  • Insanity
  • Automatism
  • Intoxication
• General Defences:

  • The circumstances of the crime are such that it would not be right, just or fair to punish the defendant for their actions.
  • Self-defence
  • Necessity
  • Consent
  • Duress
• Insanity - rules for defence were set out by House of Lords 1843. Are referred to as "M'Naghten Rules"

  • "in all cases every man is presumed to be sane and to possess a sufficient degree of reason to be responsible for his crimes."
  • However, if on balance of probabilities he is found to be "labouring under such a defect of reason, from a 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 what he was doing was wrong" then he may be not guilty by reason by of insanity
• Elements of Insanity:

  1. A Defect of Reason
  2. Caused by a Disease of the Mind
  3. Meaning D either:

  • Does not know the nature and quality of their actions, or
  • Does not know that their actions are wrong
• Defect of Reason:

  • D must be completely deprived of the power of reasoning.
  • R v Clarke 1972
  • R v Sullivan 1984
• Defect of Reason - R v Clarke 1972:

  • Where D is capable of reasoning but has failed to use those powers it is not a defect of reasoning.
  • It has to be more than absentmindedness or confusion.
  • This was the woman who stole the mincemeat as she "forgot to pay"
  • Her attempt to claim insanity was rejected - found guilty.
• Defect of Reason - R v Sullivan 1984:

  • The defect of reason can be temporary or permanent, as long as it exists at the time D did the criminal act.
  • Here this was caused by epilepsy, where D was not in a permanent state of epilepsy but it was "transient and intermittent"
  • This was still classed as insanity.
• Disease of the Mind:

  • The defect of reason must be caused by a disease affecting the mind.
  • This is legal definition - not a medical one.
  • Can be mental illness, or physical illness which affect the mind.
  • R v Kemp 1956
  • R v Sullivan 1984
  • R v Burgess 1991
  • R v Coley 2013
  • R v Hennessey 1989
• Disease of the mind (condition - yes/no if included):

  • R v Kemp 1959 (Hardening of arteries - Yes) - it affected D's mental faculties of reason, memory and understanding, even though it was not a brain condition.
  • R v Sullivan 1984 (Epilepsy - Yes) - the source of the disease is irrelevant. It could be 'organic, as in epilepsy, or functional'.
  • R v Burgess 1991 (Sleep walking - Yes) - sleepwalking as a result of a sleep disorder is classed as insanity. However if it is caused by an external factor (e.g. being hit on head), it not included.
• Disease of the mind (condition - yes/no if included):

  • R v Coley 2013 (Psychotic episode due to cannabis - No) - voluntary intoxication is an external factor and cannot be classed as insanity - even if it leads to a psychotic episode.
  • R v Hennessey 1989 (Diabetes - Yes) - hyperglycaemia from diabetes was seen as an internal factor which was then classed as insanity
• Disease of the Mind:

  • For insanity, must be proven tha the disease of the mind is caused by internal factors.
  • Therefore, any external factors leading to D's behaviour will be disregarded and insanity cannot be used.
  • This has caused confusion in diabetes cases.
• Means D does not know nature and quality of act, or that it was wrong:

  • The defence is successful if either:

  1. D did not know the nature and quality of the act they were doing, OR
  2. D did not know what they were doing was legally wrong
• Means D does not know nature and quality of act, or that it was wrong - D did not know the nature and quality of the act they were doing:

  • Could be because D is:
  • Conscious but does not know what he is doing because of his mental state
  • Unconscious or in impaired consciousness so is not aware of their own actions.
  • Example - A man sliced his wife's throat thinking ti was a loaf of bread (R v Codere)
• Means D does not know nature and quality of act, or that it was wrong - D did not know the nature and quality of the act they were doing:

  • This refers to knowing their actions are illegal.
  • If D knows their actions are illegal they cannot use defence of insanity.
  • Is the case even is their condition makes them think their actions are morally correct.
  • R v Oye 2013:
  • Attacked police during psychotic episode as he believed they were demons and evil spirits and he was saving the world.
• The outcome of using the defence is a verdict of: NOT GUILTY BY REASON OF INSANITY

  • Following the Criminal Procedure (Insanity and Unfitness to Plead) Act 1991 as amended by s.24 Domestic Violence, Crime and Victims Act 2004, this gives a judge the option to impose one of the following:

  1. Hospital Order - this is the only option for murder charge, this can be for a set time or an indefinite time.
  2. Supervision Order - usually involves treatment programme
  3. Absolute Discharge - D walks away with no further punishment.