Whitehorn v the Queen

The High Court of Australia considered an appeal by Whitehorn against his conviction for armed robbery. The dispute arose from an incident where Whitehorn was alleged to have robbed a service station while armed with a firearm. Whitehorn maintained his innocence, arguing that he was not the perpetrator of the robbery.

The central legal issue before the High Court was whether the trial judge had erred in admitting evidence of a prior conviction of Whitehorn for a similar offence. Specifically, the court had to determine if this evidence was unfairly prejudicial to the appellant and therefore inadmissible, or if it was relevant to establishing identity and thus properly admitted.

The High Court, by majority, held that the admission of the prior conviction evidence was an error. The majority reasoned that while the evidence might have had some relevance to identity, its prejudicial effect on the jury was substantial. The similarity between the prior offence and the charged offence created a significant risk that the jury would infer guilt based on Whitehorn's past conduct rather than on the evidence relating to the current charge. The court applied the principle that evidence of prior convictions is generally inadmissible unless it has a strong probative value that outweighs its prejudicial effect, particularly when the prior conviction is strikingly similar to the offence charged.

The High Court allowed the appeal, quashed the conviction, and ordered a new trial.