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Voluntary Manslaughter: Diminished Responsibility

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Voluntary Manslaughter: Diminished Responsibility

[Flash Card 1 of 3]

  • D would otherwise be guilty murder / plead partial defence / guilty of manslaughter / more sentencing discretion
  • introduced / extend limited insanity (S2(1) Homicide Act 1957 (HA 1957)) / amended by S52 CJA 2009
  • abnormality mental functioning / recognised medical condition / substantially impair reasoning

Abnormality of Mental Functioning:

  • abnormality of mental functioning / replaces old term abnormality of mind
  • Lord Parker / defined abnormality of mind / .. a state of mind so different from that of ordinary human beings that the reasonable man would term it abnormal.. (Byrne)
  • likely same standard of abnormality / test D's mental functioning so different from ordinary / reasonable man term it abnormal

Recognised Medical Condition:

  • broad / physical & psychological conditions
  • pre-menstrual tension (English) / post natal depression (Reynolds) / Battered Woman's Syndrome (Ahluwalia)
  • medical evidence must confirm / abnormality of mental functioning / caused by recognised medical condition
bits of law

Voluntary Manslaughter: Diminished Responsibility

[Flash Card 2 of 3]

Substantially Impair:

  • D's abnormality of mental functioning / must substantially impair mental responsibility for conduct / term unchanged from HA 1957
  • substantial not mean total nor minimal / jury to decide / question of fact judge may withdraw point from jury / if no evidence (Lloyd)
  • impairment must be / understanding nature of his conduct / forming a rational judgement / exercising self control
  • understand nature conduct / D is acting automatically / not aware of his conduct / suffering delusions or severe learning difficulties
  • form rational judgement / D does know nature of conduct / cannot form rational judgement / suffering paranoia or schizophrenia (Martin)
  • exercise self control / D sexual psychopath strangled and mutilated V (Byrne)
  • must be proved / substantial impairment / provides an explanation for D's conduct / causal connection introduced (CJA 2009)
  • abnormality of mental functioning / not need to be only factor / must be a substantial one
bits of law

Voluntary Manslaughter: Diminished Responsibility

[Flash Card 3 of 3]


  • general rule / intoxication cannot support diminished responsibility
  • alcohol or drugs not sufficient / to amount to injury (medical condition) / effect transient (Di Duca)
  • abnormality of mental functioning / must be caused by recognised medical condition / wording strengthens /limits jury discretion (CJA 2009)
  • further complications / D suffers some abnormality of mental functioning & intoxicated / D must satisfy jury abnormality of mental functioning substantially impaired mental reasoning / at time of the killing
  • Lord Hutton / .. the important question is: did that abnormality substantially impair his mental responsibility for his acts in doing the killing?.. (Dietschmann)
  • D intoxicated may be irrelevant (Robson) (Hendy)
  • further consideration / if D suffering from drug or alcohol addiction & dependency / key factor control over intoxication
  • Alcohol Dependence Syndrome (ADS) / recognised medical condition / sufferer cannot control their drinking
  • D was an alcoholic / drunk nearly a whole bottle of vodka before killing / D's murder conviction upheld / evidence showed D exercised control over drinking that day (Tandy)
  • voluntariness / whether D's alcohol dependency caused brain damage / important in jury directions (Wood) (Stewart)
  • jury must consider / was D suffering from abnormality of mental functioning / was this caused by ADS / was D's mental responsibility substantially impaired / was abnormality cause or significant factor in causing D to kill V
bits of law
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