Diminished Responsiblity

• s.52 Coroners and Justice Act 2009 - D suffers from an abnormality of mental functioning, from a recognised medical condition, which substantially impairs their mental ability and provides an explanation for their actions
• Stage 1: D is suffering from an abnormality of mental functioning - s.52(1)

  • Byrne - A state of mind that a normal person would find abnormal
• Stage 2: Arises from a recognised medical condition - s.52(1)(a)

  • Brennan - Must provide medical evidence
  • Tandy - Alcohol dependency syndrome
  • Ahluwhalia - Battered wife syndrome/domestic abuse
  • Seers - Depression
  • Martin - Personality disorder
  • Kay - Schizophrenia
• Stage 3: Substantially impairs D's ability to

  • Understand the nature of their conduct e.g. delusions
  • Form a rational judgement e.g. paranoia, depression
  • Exercise self-control e.g. irresistible impulse
• Stage 4: Abnormality provides an explanation for D's conduct

  • Must be a causal connection from your abnormality to the killing (significant factor in the cause of your killing)
• Side rule - diminished responsibility and intoxication

  • If D has an abnormality and is also drinking, only focus on the abnormality - was the abnormality alone enough to substantially impair their mental responsibility? (Dietschmann)