Washer v Western Australia

In *Washer v Western Australia*, the High Court of Australia considered an appeal by Raymond Washer against his conviction for conspiracy to possess a prohibited drug with intent to sell or supply. Washer had previously been acquitted of a separate conspiracy charge involving different times and parties, but some of the evidence, described as "drug dealing evidence," was admitted in his second trial. This evidence tended to show Washer was a drug dealer and had been presented in his first trial.

The central legal issues before the High Court were whether the "drug dealing evidence" was relevant to the offence charged in the second trial, and whether evidence of Washer's prior acquittal was relevant and admissible. The trial judge had admitted the drug dealing evidence, holding it was relevant to proving intent to sell or supply and to rebut claims of innocent association. The judge also directed the jury not to use this evidence to infer that a person who dealt drugs on one occasion was more likely to do so subsequently.

The High Court, in a joint judgment, acknowledged that while evidence of a prior acquittal can be relevant and admissible in certain circumstances, particularly when overlapping evidence is used, it was not so in this case. The Court affirmed the principle that when evidence tending to prove an earlier charge is admitted in a subsequent charge, the jury must be warned not to use that evidence to question or discount the effect of the earlier acquittal. This principle is rooted in legal policy, recognising the conclusiveness of an acquittal between parties and protecting an accused from repeated vexation.

Despite finding that the appellant had made good his complaint regarding the refusal to permit proof of his earlier acquittal and a direction to the jury on its use, the High Court dismissed the appeal. This was on the basis that, in the circumstances of overwhelming evidence of guilt in the second trial, the case was one for the application of the "proviso" under the Criminal Appeals Act 2004 (WA), meaning the conviction would be upheld despite the error.