Diminished responsibility

Diminished responsibility

Under the S.52 of the Coroner's and Justice Act 2009 which substitute S.2 of the Homicide Act 1957, diminished responsibility is available as a defence to defendants who are suffering from an abnormality of mental functioning (AOFM) which;

(1) Arose from a recognized medical condition which (2) substantially impaired  his/her ability to; understand the nature of his/her conduct, form a rational judgment or/and exercise self control which (3) provides an explanation for his/her acts and omissions in doing or being a party to the killing.

(AOMF) R v Byrne states that the "state of mind is so  different from that of an ordinary person that the reasonable man would term it abnormal".

(1) Recognized medical condition means that it must be recognized in WHO (World Health Organization) classification of psychiatric conditions.

(2) R v Lloyd states that substantial impairment "need not to be total but must be more trivial or minimal". However, R v Byrne states whether the defendant is substantially impaired or not is a question for the jury to decide.

(3) S.1B of Homicide Act 1957 states abnormality of mental functioning  must be the "significant contributory factor for causing the a defendant to carry out that conduct".

Intoxication

- R v Tandy held that the intoxication must reached to a level where it causes brain damage that it causes irresistible urges to drink to the defendant. This precedent have been criticized for being "too high" by then Lord Justice Judge.

- R v Wood recognized Alcohol Dependency Syndrome (ADS) can be an abnormality of mental functioning.

- R v Stewart held that the defendant must be suffering from abnormality of mental functioning that is caused by ADS and this substantially impaired the defendant mental responsibility.

- R v Dietschmann held that a jury can return a guilty verdict on the grounds of manslaughter on the grounds of diminished responsibility, provided there is evidence that the tests for diminished responsibility is satisfied. This defence will only apply to defendants with an abnormality of mental functioning and had also consumed alcohol but do not have ADS.