Murphy v Helmling (No 2)

In Murphy v Helmling (No 2), the appellant challenged the conviction for driving with a prescribed drug in his oral fluid, contending that he was unaware of the presence of the drug due to an honest mistake. The case was heard by the District Court of New South Wales, which upheld the conviction, and subsequently, the appellant appealed to the Supreme Court of New South Wales.

The central legal issue was whether the appellant’s unawareness of the presence of the prescribed drug could constitute a defence. This involved examining the principles of mistake of fact in criminal law and whether the presence of the drug could be attributed to intervening conduct or events. The court had to determine if the mistake of fact defence could be applied in cases of driving with a prescribed drug in one's oral fluid, and if so, under what circumstances.

The Supreme Court of New South Wales held that the appellant's mistake of fact defence was not available in this context. The court reasoned that the appellant’s lack of knowledge about the drug did not negate the objective fact of its presence in his oral fluid at the time of driving. The court emphasised that the presence of the drug was the critical factor, not the driver's knowledge or intention. Therefore, the appeal was dismissed, and the conviction upheld. The court also made the usual orders that the informant pay the defendant’s costs.