Police v Dunstall

The High Court of Australia heard an appeal concerning a charge of driving a motor vehicle with a prescribed concentration of alcohol. The appellant, the Police, sought to tender evidence of a breath analysis reading, which indicated a blood alcohol level above the legal limit. The respondent, Mr Dunstall, had arranged for a blood sample to be taken, but it was subsequently unable to be analysed through no fault of either party. Mr Dunstall argued that admitting the breath analysis reading would render his trial unfair, particularly as the inability to analyse the blood sample prevented him from rebutting the presumption created by the breath analysis.

The central legal issue before the High Court was whether a residual common law discretion exists to exclude lawfully obtained, probative, and non-confessional evidence, where its admission would render the trial of the accused unfair. This involved considering the scope of the "fairness discretion" in criminal proceedings, particularly in light of statutory provisions that modify common law rules of evidence, such as those creating presumptions regarding breath analysis readings. The Court had to determine if the specific circumstances of Mr Dunstall's case, where the intended rebuttal evidence was rendered inadmissible due to circumstances beyond his control, constituted "forensic unfairness" that warranted the exclusion of the prosecution's evidence.

The High Court allowed the appeal, holding that the fairness discretion does not exist to give effect to idiosyncratic notions of "fair play" or to allow a judge to disapprove of statutory modifications to common law proof. The discretion is intended to prevent a miscarriage of justice by excluding evidence that carries an unacceptable risk of unfairness. In this instance, the Court found that the inability to analyse the blood sample, while unfortunate, did not create an unacceptable risk of miscarriage of justice through the admission of the breath analysis certificate. The Court reasoned that the trial would still be conducted according to law, including the statutory presumptions, and that the respondent had not been deprived of a fair trial in the relevant legal sense.

Consequently, the High Court set aside the order of the Full Court of the Supreme Court of South Australia and remitted the matter to the Magistrates Court for further hearing. The Police were ordered to pay Mr Dunstall's costs in the High Court.