Jury Verdict Reasoning and Cassation Review in Spain: STS 58/2026

STS 58/2026, delivered on 29 January 2026 in appeal 2647/2023, addresses two central questions of Spanish jury-trial procedure: the standard of reasoning that can be demanded of a verdict, and the scope of the review that the Supreme Court carries out when the case reaches cassation after having already gone through an appeal. Analysing this ruling helps to understand the logic of the two-tier review that defines this procedural channel.

The two-tier review: appeal and cassation in jury proceedings

The jury-trial process set out in Organic Law 5/1995 provides for a two-stage challenge structure. The presiding judge's judgment may be appealed to the High Court of Justice (Tribunal Superior de Justicia), which has full power to review both the factual and the legal aspects of the case. Once that appeal is resolved, the High Court's judgment may be challenged in cassation before the Supreme Court.

This two-tier structure has a fundamental consequence: when the Supreme Court examines the matter in cassation, it does so on the basis of a decision — the appeal judgment — that has already subjected the proven facts to an exhaustive review. That is why access to cassation in this channel is more restricted than in ordinary proceedings: this is not a second appeal, but a lawfulness review of the decision that closed the ordinary avenue of challenge.

Verdict reasoning: what the jurors must express

Article 61.1.d) of the Jury Court Organic Law (LOTJ) requires the verdict record to express the elements of conviction and a brief explanation of the reasons why the jurors have declared certain facts proved or not proved. STS 58/2026 recalls that this requirement does not impose on lay jurors a technically elaborate form of reasoning equivalent to that of a professional judge, but it does require them to identify the evidence on which they relied.

This requirement serves an essential protective function: it allows both the parties and the reviewing courts to verify that the verdict is not arbitrary but is the product of deliberation resting on prosecution evidence gathered and taken with the guarantees of a fair trial. A generic reference to "all the evidence adduced" without identifying any of it is insufficient.

The role of the presiding judge in the judgment

The presiding judge's role is not confined to pronouncing the sentence. Once the verdict is known, it falls to the judge to draft the judgment, expanding and completing the jury's reasoning. The judge must give legal form to the facts the jurors declared proved, subsume the conduct within the applicable offences, fix the sentence and rule on civil liability.

STS 58/2026 confirms that the verdict reasoning and the presiding judge's judgment form an inseparable whole. The subsequent review of that reasoning cannot separate what the jurors expressed from what the judge developed: both components complement each other and must be read together. If the verdict record is brief, the judge's judgment must be more thorough so that the overall document is sufficiently reasoned.

The Supreme Court's review in cassation: lawfulness, not fresh assessment

Having confirmed the principle that cassation only controls the lawfulness of the appeal judgment, STS 58/2026 applies this criterion consistently. The appeal sought to have the Supreme Court review the assessment of the evidence and the factual account fixed by the trial court and upheld on appeal. The Chamber rejects this clearly: cassation is not the appropriate channel for reopening that debate.

What the Court does examine, however, is whether the aggravating circumstances applied to the counts of attempted homicide met the requirements prescribed by law and case law. Here the Supreme Court does not alter the proven facts; it checks whether the legal classification — the application of the aggravating factors — respected those requirements. Finding that the aggravating circumstances were not present, the Chamber reduces the sentence without contradicting the already final factual record.

Convictions upheld and sentence reduced on specific counts

STS 58/2026 upholds the convictions for murder (Articles 138 and 139 CP). On the counts of attempted homicide, the Court finds that the aggravating circumstances applied lacked the required elements and reduces the sentence on those specific offences. The outcome is a ruling that largely leaves the convictions intact, correcting only the excess in the penalty for the attempted offences.

This result illustrates a practical feature of cassation appeals in jury-trial proceedings: the prospects of success are greater when the challenge targets a defect of lawfulness in the legal classification — incorrect application of offence definitions, aggravating or mitigating factors — than when it seeks a review of the factual account or the assessment of the evidence already examined on appeal.

Implications for criminal defence in jury proceedings

The doctrine of STS 58/2026 has direct consequences for defence strategy in jury-trial cases. At first instance, the defence should ensure that the verdict record adequately sets out the evidence relied upon: an insufficiently reasoned verdict can be a ground of appeal. On appeal, that is the moment to challenge both the facts and the legal classification, since the High Court has full jurisdiction to review both. In cassation, the effort should focus on defects of lawfulness in the appeal judgment, without seeking to reopen the factual debate that has already been exhausted.