Appeal court rules forensic evidence of penetration can corroborate rape allegation – even where consent is disputed

About this case:

• Citation:
  [2026] HCJAC 42
• Judgment:
  External link
• Court:
  Appeal Court of the High Court of Justiciary
• Judge:
  Lord Pentland

In a significant ruling clarifying the modern law of corroboration, the court held that scientific evidence confirming penetration can support the whole case against an accused without separately establishing an absence of consent. It emphasised, however, that both the commission of the offence and the identity of its perpetrator must still be corroborated.

The lord advocate sought authoritative guidance following the conviction of PK on ten charges, including eight charges of rape and sexual assault involving two complainers. The case raised questions about the practical application of the full bench decision in Lord Advocate’s Reference No 1 of 2023, which established that individual elements of a criminal offence did not each require separate corroboration.

The reference was heard by the Lord Justice General, Lord Pentland; the Lord Justice Clerk, Lord Beckett and Lord Matthews, with the Solicitor General for Scotland, BJ Gill KC and advocates depute Harvey and Cox appearing for the Crown. Jones KC, Loosemore and Simpson, instructed by the Public Defence Solicitors’ Office in Dundee, appeared for PK.

Forensic evidence of penetration

At PK’s trial, the Crown led evidence from two forensic biologists concerning samples taken from one of the complainers, VW, following separate incidents in January 2019 and January 2023. Dr Jonathan Bevan testified that sperm cells attributable to PK had been recovered from high vaginal swabs taken the day after the first incident. Dr Sarah Milne gave similar evidence concerning semen recovered from samples taken shortly after the second. PK denied raping VW, maintaining that whenever they had sexual intercourse it had been consensual.

The trial judge directed the jury that the scientific evidence was capable of corroborating VW’s account of rape. Following his conviction, PK challenged that direction in an appeal against conviction but abandoned the appeal shortly before it was due to be heard. The lord advocate subsequently referred four questions to the Appeal Court under section 123(1) of the Criminal Procedure (Scotland) Act 1995. They concerned whether scientific evidence of penetration, DNA recovered from a complainer’s clothing or breasts, and other direct or circumstantial evidence could corroborate allegations of rape or sexual assault where that evidence did not independently demonstrate a lack of consent.

Scope of the 2023 ruling

For the Crown, it was submitted that the questions were answered by the 2023 full bench decision. Corroboration did not require each constituent element of an offence to be separately established by two sources of evidence. Rather, a second source needed only to support or confirm the complainer’s account. The Crown maintained that circumstantial evidence was capable of doing so even if, considered independently, it was equally consistent with innocence.

For PK, it was argued that evidence confirming penetration alone could not corroborate rape because it established nothing about consent. The defence submitted that the independent evidence had to be capable, when considered alongside the other evidence, of supporting an inference that the offence had been committed. To hold otherwise, it maintained, would reduce the requirement for corroboration to a formality in cases where sexual intercourse was admitted but consent remained disputed.

Delivering the court’s opinion, Lord Pentland examined the development of corroboration in Scots law, including the twentieth-century requirement that each essential element of an offence be independently corroborated. That approach had culminated in Smith v Lees, which was overruled by the seven-judge bench in Lord Advocate’s Reference No 1 of 2023. Lord Pentland explained that the court’s present responsibility was to apply the law established by that authoritative decision, rather than undertake a fresh examination of corroboration.

Evidence need not independently establish criminality

Rejecting PK’s argument, the court held that it incorrectly isolated the corroborative evidence from the complainer’s testimony and effectively reintroduced the requirement to corroborate individual elements of an offence. Lord Pentland said: “The second source of evidence needs to fit with the complainer’s account. It does not need to point towards the commission of the crime charged.” Continuing, he added: “Looked at in isolation, the second source will often be entirely neutral in the sense that it does not yield any inference of criminality.”

The court drew an analogy with independent evidence of a complainer’s distress following an alleged rape. Such evidence had already been recognised as capable of corroborating the whole offence under the 2023 decision, notwithstanding that distress alone revealed nothing about whether sexual intercourse had occurred.

By the same reasoning, evidence confirming penetration could corroborate the complainer’s account of rape without independently demonstrating an absence of consent. Lord Pentland explained that where penetration by the accused was established through forensic evidence, that evidence provided a second source capable of supporting the complainer’s direct testimony. The two sources, considered together, could therefore provide a legal sufficiency of evidence that rape had occurred.

It remained for the jury to decide whether to accept the evidence and whether it genuinely supported the complainer’s account. A conviction could follow only where the jury was satisfied of guilt beyond reasonable doubt.

DNA evidence and admissions

Applying those principles to the questions referred, the court held that forensic evidence confirming penile penetration of a complainer’s vagina could corroborate her account of rape. It also confirmed that scientific evidence of an accused’s DNA on a complainer’s clothing or breasts could corroborate allegations of sexual assault or assault with intent to rape. The same principles applied to an accused’s admission that sexual intercourse had taken place, even where the admission was accompanied by an assertion that it had been consensual. Such a statement could corroborate the complainer’s account because it confirmed the occurrence of sexual intercourse. The inclusion of an innocent explanation did not automatically deprive it of corroborative value.

The jury would, however, have to consider that explanation and be satisfied that the Crown had displaced it before relying upon the admission in convicting the accused. More generally, the court confirmed that evidence previously regarded as corroborating only one element of an offence could now corroborate the commission of the offence as a whole. The identity of the accused as its perpetrator remained a separate matter requiring corroboration.

Corroboration remains a safeguard

Lord Pentland rejected the suggestion that the approach rendered corroboration an empty formality. Independent support for a complainer’s testimony remained necessary, and the jury was required to assess both the quantity and quality of the evidence. He stated: “The requirement for corroboration remains an important safeguard under Scots law.”
The court answered all four questions referred by the lord advocate in the affirmative, subject to the qualification that the commission of the offence and the identity of the accused must each be proved by corroborated evidence. In a concluding observation, Lord Pentland acknowledged that cases in which scientific evidence of penetration or sexual assault provided the only available corroboration were likely to be rare.

In PK’s original trial, mutual corroboration had been available on every charge. Other supporting material included evidence of distress, statements made shortly after some incidents and medical evidence of injury.

The court nevertheless confirmed that, following the 2023 ruling, a second source of evidence need not itself establish criminality to be capable of corroborating a complainer’s account.