R, R. v

For diminished responsibility under Homicide Act 1957, “substantially” bears its ordinary meaning. The impairment must be more than trivial, but need not be total. Whether mental responsibility was substantially impaired is a question of degree for the jury, assessed on all the evidence.

A trial judge should convey the statutory language without exaggerating the defendant’s burden or adding a non-statutory requirement. Different conventional explanations of substantial impairment are permissible where they express the same concept. The word is not impermissibly uncertain, and does not give rise to an Article 7 issue.

The appellant killed his cousin after planning a meeting and using a ligature. At his second trial in the Crown Court at Ipswich, the sole issue was whether a depressive disorder had substantially impaired his mental responsibility, so as to reduce murder to manslaughter by diminished responsibility.

Both psychiatric experts accepted that he had an abnormality of mind. They disagreed about whether it substantially impaired his responsibility. The jury convicted him of murder on 9 September 2008 and he received life imprisonment with a minimum term of 12 years.

He appealed on the basis that the directions on “substantially impaired” were ambiguous and incompatible with Article 7. He also renewed his application for leave to appeal the minimum term.

1. The appeal against conviction was dismissed. Section 2(1) of the Homicide Act 1957 uses an ordinary English word. “Substantially” excludes an impairment which is trivial or insignificant, but does not require mental responsibility to have been extinguished. The issue remains one of degree for the jury.
2. The jury must decide the issue on the whole evidence. Medical evidence is relevant, but does not displace the jury’s own assessment. The trial judge’s task is to convey the statutory question in plain language, without increasing the defendant’s burden or imposing an additional requirement.
3. The conventional directions approved in R v Lloyd [1967] 1 QB 175 did not identify two alternative legal meanings of “substantially”. They were different ways of explaining the same ordinary concept. Judge Devaux’s original direction, and his further direction that substantial impairment lay between trivial and total impairment, were consistent and accurate. The further direction did not prejudice the appellant’s submissions.
4. There was no uncertainty or ambiguity in the statutory language. Accordingly, no issue under Article 7 of the European Convention on Human Rights arose.
5. The court added that Judicial Studies Board specimen directions are valuable guidance, but are not binding authority unless this court has approved or adopted them.
6. The renewed application for leave to appeal sentence was refused. The sentencing judge had properly treated planning and intent to kill as aggravating. The stress and reduced mental acuity arose from the same source and were properly assessed collectively as mitigation. The 12-year minimum term was neither manifestly excessive nor wrong in principle.

• Court of Appeal (Criminal Division): The appeal against conviction was dismissed and the renewed application for leave to appeal against sentence was refused.
• Crown Court at Ipswich: On 9 September 2008, the appellant was convicted of murder following a second trial. He was sentenced the following day to life imprisonment with a 12-year minimum term.