MF, R v

Fresh psychiatric evidence may be admitted under section 23 of the Criminal Appeal Act 1968 where its admission is necessary or expedient in the interests of justice. The court must have particular regard to its credibility, admissibility, capacity to afford a ground of appeal, and the explanation for its absence at trial.

Where credible and unchallenged expert evidence establishes that a defendant's mental responsibility was substantially impaired at the time of a killing, and there is a reasonable explanation why diminished responsibility was not advanced at trial, a murder conviction may be unsafe. The proper course is to quash that conviction and substitute manslaughter on the ground of diminished responsibility.

The appellant, aged 17 at the time, was convicted of murder at Chelmsford Crown Court after a trial before Thomas J. His earlier appeal against conviction, concerning the jury's understanding of provocation, had been dismissed.

Following a reference by the Criminal Cases Review Commission, the appellant relied on fresh psychiatric evidence. Two consultant adolescent forensic psychiatrists concluded that, at the time of the killing, he had an abnormality of mind arising from depressive, adjustment and post-traumatic stress disorders which substantially impaired his mental responsibility. The issue was whether that evidence should be admitted and, if so, whether the murder conviction remained safe.

1. Appeal allowed. The Vice-President, giving the judgment of the court, held that the fresh psychiatric evidence should be received under section 23 of the Criminal Appeal Act 1968.

2. The statutory considerations in section 23(2) were satisfied. The evidence was capable of belief, admissible, and capable of affording a ground for allowing the appeal. There was also a reasonable explanation for its absence at trial. The only psychiatrist then instructed did not have apparent specialist adolescent psychiatric expertise, was not asked to develop his assessment, and diminished responsibility was neither raised nor discussed with the appellant. This was not a tactical decision to forgo that defence.

3. The appellant's incomplete disclosure of the sexual abuse at trial did not undermine that explanation. The later expert evidence explained that trauma could impede disclosure, including disclosure to legal representatives. The Crown did not resist admission or challenge either psychiatrist's conclusions, and oral evidence would have served no useful purpose.

4. The unchallenged evidence established that the appellant's mental responsibility was substantially impaired when he killed the deceased. Had properly qualified psychiatric evidence been obtained at trial, there was a high probability that the Crown would have accepted a plea of guilty to manslaughter on that ground. The murder conviction therefore could not safely stand.

5. The court quashed the murder conviction and substituted a conviction for manslaughter by reason of diminished responsibility. It imposed seven years' imprisonment, which the appellant had already served in equivalent time.

• Court of Appeal (Criminal Division): Following a reference by the Criminal Cases Review Commission, allowed the appeal, quashed the murder conviction, and substituted manslaughter by reason of diminished responsibility.
• Full Court (differently constituted): On 24 July 1998, dismissed the earlier appeal against conviction, which concerned the direction on provocation.
• Chelmsford Crown Court: On 10 October 1997, following a trial before Thomas J, convicted the appellant of murder and sentenced him to detention during Her Majesty's pleasure.