- A person who kills or is party to a killing of another is not to be convicted of murder of he was suffering an abnormality of mental functioning which:
- b) substantially impaired D's ability to: understand the nature of his conduct or form a rational judgement or exercise self control
- a) arose from a recognised medical condition
- BYRNE - 'State of mind so different from the ordinary human beings that the reasonable man would term it abnormal
- c) provides an explanation for D's acts and omissions in doing or being party to the killing.
- Recognised medical conditions include : depression, paranoia or battered woman's syndrome.