R v Victor Mazzer

Expert evidence about post-traumatic stress disorder may be relevant to self-defence where it assists the jury’s assessment of the defendant’s perceived threat and use of force. The report must nevertheless be sufficiently reliable, reasoned and tethered to the evidence of what occurred. A general diagnosis and an account of possible effects will not assist where it does not relate those effects to the defendant’s trial account.

A judge need not direct on defence of another unless that defence arises on the evidence. Fresh evidence which does not provide an arguable basis for impugning a conviction does not justify an extension of time to seek leave to appeal.

At Inner London Crown Court, the applicant was convicted of two offences of causing grievous bodily harm with intent after a street disturbance following a house party. His case at trial was self-defence. He said that he had been attacked and had waved a kitchen knife to deter his attackers, without intending to injure anyone.

After conviction, a psychologist diagnosed post-traumatic stress disorder arising from an earlier assault. The condition was treated as mitigation at sentence. The applicant renewed, after the single judge’s refusal, an application for an extension of time to seek leave to appeal against conviction. He sought to adduce the psychologist’s updated report under section 23 of the Criminal Appeal Act 1968. He also contended that the jury should have been directed on defence of another.

1. The court refused the extension of time and all applications to adduce fresh evidence. Neither proposed ground provided an arguable basis for concluding that the convictions were unsafe.

2. R v Press and Thompson [2013] EWCA Crim 1849 established that PTSD may be relevant to self-defence. It may bear on whether a defendant honestly believed that an attack or threat existed, and on the assessment of the force used. That potential relevance did not make Professor Farrell’s evidence admissible or capable of undermining these convictions.

3. Applying the approach in R v B (MA) [2013] 1 Cr App R 36 and R v BRM [2022] EWCA Crim 385, an expert report must be sufficiently reliable, explain its reasoning and be tethered to the evidence of the events, including the defendant’s account. Professor Farrell’s report did not relate PTSD or hypervigilance to any particular circumstance described at trial. It did not address the taking of the knife, and the applicant did not suggest that PTSD caused him to miscalculate a threat. His evidence was instead that he was actually being attacked. The report would therefore not assist the jury on the issue they had to decide.

4. The applicant had never said that he believed Gabriel Garland was under attack or that he used the knife to protect him. Defence of another did not arise on the evidence. The trial judge was not required to give a direction on that unraised defence.

5. Under section 23(3) of the Criminal Appeal Act 1968, the proposed fresh evidence afforded no arguable ground for allowing an appeal against conviction.

• Court of Appeal (Criminal Division): The court refused the renewed application for an extension of time to seek leave to appeal against conviction and refused the applications to adduce fresh evidence.
• Crown Court at Inner London: On 2 March 2023, the applicant was convicted of two offences of causing grievous bodily harm with intent. On 14 April 2023, he received concurrent sentences of 42 months’ imprisonment.