John Eder Riley v Garth Christian Seip

The case of John Eder Riley v Garth Christian Seip involved the defendant appealing against his conviction for driving with a prescribed concentration of alcohol in his blood. The matter was heard in the Court of Appeal, having originated from a decision made by a magistrate. The central issue revolved around the reliability and calibration of the Drager breath analysing instrument used to measure the defendant’s blood alcohol concentration. The defendant argued that the breathalyser reading was not reliable due to potential calibration issues.

The court examined the legal principles underpinning the use of breathalyser readings in such cases, focusing on the certification of the breathalyser reading as prima facie evidence of the presence of the prescribed concentration. The evidential burden was on the prosecution to prove the defendant had driven with the prescribed concentration of alcohol in his blood, while the defendant needed to cast a reasonable doubt on the result obtained by the breathalyser.

The Court of Appeal dismissed the appeal, confirming the magistrate's orders. The court held that the evidence provided by the breathalyser reading, coupled with the other evidence of intoxication and alcohol consumption, sufficiently supported the conviction. The court found that the calibration and reliability of the breathalyser did not undermine the validity of the reading. Consequently, the defendant’s conviction was upheld, with the disqualification order and time for payment dating from 12 August 2008.