defences of diminished responsibility

• where was diminished responsibility introduced?

  homicide act 1957
• what was diminished responisibilty amended in?

  s52 coroners and justice act 2009
• what does diminished responsibility state in CAJA 2009?

  a person who kills or is a party to the killing of another is not to be convicted if he or she was suffering from an abnormality or mental functioning which:

  a arose from a recognised medical condition

  b substantially impaired ds ability to

  understand his nature of his conduct or

  form a rational judgement or

  exercise self control

  c provides an explanation for the d is on the d, but the d need only prove it on the balance of probabilities
• what is the.four stage test?

  1 d was suffering from an abnormality of mental functioning

  2 if so, whether it had raised from a recognised medical condition

  3 if so, whether it had substantially impaired their ability either to understand the nature of their conduct, or rational judgement, or exercise self control

  if so, whether it provided an explanation for their conduct
• "abnormality of mental functioning"


  r v bryne: " a state of mind so different from that of an ordinary human beings that the reasonable man would term it abnormal"

  recognised medical conditions examples:

  depression- r v gittens

  battered spouse syndtome- r v ahluwalia

  epilepsy- r v campbell
• "recognised medical condition"


  introduced inti s2 of the 1957 homicide Act

  recognised medical conditions examples:

  depression- r v gittens

  battered spouse syndtome- r v ahluwalia

  epilepsy- r v campbell

  autism spectrum disorder- r v conroy

  paranoid personality disorder- r v squelch
• "substantially impaired"


  the abnormality of mental functioning must substantially impair the ds mental responsibility for his acts or omissions in doing or being apart of the killing

  r v golds
• what must be substantially impaired?

  s2 (1a) of the homicide act 1957

  1 to understand his nature or conduct

  2 ability to form a rational judgement

  3 ability to exercise self control
• understand the nature of his conduct


  covers situations such as where the d is in a automatic state- does not know what they are doing or suffers from delusions

  also covers severe learning difficulties
• ability to form a rational judgement


  those suffering from paranoia, schizophrenia or battered spouse syndrome may not be able to form a rational judgement

  jury may consider what happened before or after the killing
• ability to exercise self- control


  r v bryne- sexual psychopath
• provides an explanation for ds conduct

  CAJA 2009 states must be some casual connection between the ds abnormality and the killing

  mental functioning does not have to be the only factor which caused the d to kill
• intoxication and diminished responsibility


  1 intoxication cannot found the defence - r v dowds

  2 where the d has a pre-existing disorder, intoxication does not prevent him from using the defence- r v dietschann

  3 ADS can be an abnormality of mental functioning- r v wood