Mallard v The Queen

In *Mallard v The Queen*, the High Court of Australia considered an appeal against a conviction for murder. The appellant, Mallard, had been found guilty of the murder of his wife, and the conviction was upheld by the Supreme Court of South Australia on appeal. Mallard then sought special leave to appeal to the High Court.

The central legal issue before the High Court was whether the trial judge had erred in law by admitting evidence obtained through a search of the appellant's home, which Mallard argued was conducted unlawfully. Specifically, the court had to determine if the evidence, particularly DNA evidence found at the scene, was admissible despite potential irregularities in the search warrant or its execution. This involved considering the principles governing the admissibility of evidence obtained in contravention of statutory provisions and the common law.

The High Court ultimately granted special leave to appeal and allowed the appeal, quashing the conviction. Their Honours found that the search warrant was invalid because it had been issued without sufficient grounds. Consequently, the evidence obtained from the search was unlawfully obtained. The court held that the admission of this unlawfully obtained evidence at trial had occasioned a substantial miscarriage of justice, as it was highly prejudicial to the appellant and likely influenced the jury's verdict. The legal principle applied was that evidence obtained in contravention of the law, particularly where the contravention is significant, should generally be excluded unless its admission can be justified by compelling reasons, which were absent in this case.

The High Court ordered that the conviction be quashed and remitted the matter to the Supreme Court of South Australia for a retrial.