Daly and Keir v HM Advocate: Supreme Court rules Scottish evidence law breaches fair trial rights

The UK Supreme Court has delivered a significant judgement finding that Scotland's current approach to admitting evidence in sexual offence trials is incompatible with Article 6 of the European Convention on Human Rights, though both appeals before the Court were ultimately dismissed.

In two conjoined Scottish appeals heard under section 288AA of the Criminal Procedure (Scotland) Act 1995, the Court examined whether the High Court of Justiciary's recent development of the common law on collateral evidence and sexual behaviour evidence violated the accused's right to a fair trial. The appeals arose from rape convictions where the accused sought to introduce evidence concerning the complainers' credibility and previous sexual behaviour.

Lord Reed, delivering the unanimous judgement with which all other Justices agreed, traced the evolution of Scottish evidence law from its historical position through the enactment of sections 274 and 275 of the 1995 Act (as amended by the Sexual Offences (Procedure and Evidence) (Scotland) Act 2002) to recent restrictive developments in cases such as CJM v HM Advocate and CH v HM Advocate.

The Court identified fundamental flaws in the current Scottish approach. Since CJM v HM Advocate, the appeal court has treated evidence going to credibility as both irrelevant and collateral unless instantly verifiable (typically through extract convictions). This has effectively created a blanket exclusion of evidence that, whilst not directly bearing on the facts in issue, could strengthen the defence position—particularly problematic in sexual offence cases where the complainer's credibility is often decisive.

The judgement emphasised that this approach conflicts with established Convention jurisprudence, particularly the Grand Chamber decision in Murtazaliyeva v Russia, which confirmed that defence evidence should be admitted if it can "reasonably be expected to strengthen the position of the defence". The Court also highlighted Poropat v Slovenia, where refusing evidence going to credibility in a case dependent on witness testimony was found to violate Article 6.

Regarding sexual behaviour evidence, the Court rejected the reasoning in recent Scottish cases that prior sexual activity between parties is "prima facie unrelated" to subsequent events. Following R v A (No 2), the Court explained that such evidence may be relevant where circumstances enable an inference about the complainer's attitude towards the accused, which may bear on her state of mind at the material time. The bare fact of prior consent is not relevant, but the context of a relationship may be.

The Court was particularly critical of the conflation between the legal rule that consent must be contemporaneous and the evidential question of whether prior expressions of willingness may be relevant to assessing whether consent was given—a logical fallacy that had become embedded in Scottish practice.

Crucially, the Court held that sections 274 and 275 should be understood as creating a unified statutory scheme, not merely supplementing common law restrictions. The legislation's nuanced balancing test in section 275(1)(c) reflects Parliament's considered approach to reconciling defence rights with appropriate protection of complainers' dignity and privacy.

Despite finding the general approach incompatible with Article 6, both appeals were dismissed on their specific facts. In Daly, investigating the alleged false allegation would have required a collateral trial on a distinct issue. In Keir, the prior sexual activity had minimal probative value given the prosecution case that the complainer was asleep when assaulted, coupled with strong corroborative evidence of intoxication and distress.

The judgement requires Scottish courts to modify their approach to evidence admissibility in sexual offence cases, adopting a more nuanced assessment that gives proper weight to the defence's right to challenge evidence effectively whilst maintaining appropriate protection for complainers.

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