R v Duncan

The appeal concerned a conviction for aggravated robbery, contrary to section 137(1) of the *Criminal Law Consolidation Act 1935* (SA). The appellant, R, was convicted by a judge alone, and the case against him relied entirely on circumstantial evidence. R appealed his conviction, arguing that the verdict was unsafe and unsatisfactory, and that the trial judge had not properly considered the circumstantial evidence or whether there was a reasonable hypothesis consistent with innocence. The appeal was heard by the Full Court of the Supreme Court of South Australia, comprising Doyle CJ, Kelly J, and Peek J.

The central legal issues before the Full Court were whether the trial judge had correctly assessed the circumstantial evidence presented, and whether, when viewed in its entirety, the evidence was sufficient to prove the appellant's guilt beyond a reasonable doubt. This required the Court to consider whether the trial judge had erred in dismissing certain aspects of the defence case as mere coincidences and whether the overall improbability of the defence's narrative had been overstated. The Court was tasked with determining if there remained a reasonable hypothesis consistent with the appellant's innocence, given the evidence.

The Full Court allowed the appeal, quashing the conviction and substituting a verdict of acquittal. The Court reasoned that the trial judge had erred in characterising a list of matters as independent coincidences, finding that they were not truly independent. Furthermore, the Court concluded that the improbability of the defence's case had been significantly overestimated by the trial judge. Consequently, the Court found that the evidence adduced was insufficient to prove the charge beyond a reasonable doubt, rendering the verdict unreasonable. The Court ordered that the conviction be set aside and a judgment and verdict of acquittal be entered.