Diminished Responsibility

• Introduction

  Section 2 Homicide Act 1957 amended by Section 52 Coroners and Justice Act 2009

  A special and partial defence

  • Special as it only applies to murder
  • Partial as it reduced murder to voluntary manslaughter

  The judge has discretion on sentencing; there is a reverse burden of proof meaning the Defendant must establish the partial defence
• Stage 1: Abnormality of mental functioning

  Byrne defines this as ‘a state of mind so different from that of an ordinary human being that the reasonable man would term it abnormal’

  • Does not have to be permanent, nor have existed from birth, as long as it existed at the time the murder happened
• Stage 2: Recognised medical condition

  This covers both physical or mental condition - must be medical evidence from two experts; Bunch

  It includes (but is not limited to) conditions recognised by the World Health Organisation;

  • Depression; Gittens
  • Personality Disorders; Martin
  • Battered Women Syndrome; Ahluwalia
• Stage 3: Substantially impairs the Defendant’s ability

  Must be shown that the abnormality of mental functioning made a ‘more than minimal’ impact on the defendant’s actions;

  • Bryne tells us that it is for the jury to decide what is ‘substantial impairment’
  • Gold tells us that if the jury cannot decide this then they will be directed that ‘substantial’ means ‘significant’ or ‘more than minimal’

  The abnormality must impact the defendant’s ability to do one or more of the following;

  1. Ability to understand the nature of his conduct
  2. Ability to exercise self-control
  3. Ability to form a rational judgement
• Stage 4: Causal Connection

  The defendant must prove that there is a causal connection between the abnormality of mental functioning and the murder; the abnormality provides an explanation for the killing

  • It doesn’t need to be the only factor which caused the defendant’s conduct but it must be a significant factor
• Intoxication and Diminished Responsibility

  Intoxication alone cannot be used as the basis of a defence of diminished responsibility; intoxication is not a abnormality of mental functioning; Dowds

  • If the defendant has an abnormality and is intoxicated, jury must dismiss the intoxication and decide based on whether they would have killed without the substance; Dietchmann
  • If they have Alcohol Dependence Syndrome then this may be an abnormality, there is no need for alcohol to cause brain damage or for every drink to be involuntary; Stewart