Roads and Traffic Authority of New South Wales v Barwick

The Roads and Traffic Authority of New South Wales recently sought to appeal a local court decision that acquitted an individual, Barwick, of speeding offences. Barwick was caught speeding on a road where the speed limit was 60 km/h. However, Barwick argued that he was under the impression that the speed limit was 50 km/h, due to a misleading sign. The lower court acquitted Barwick on the basis that his belief about the speed limit constituted a genuine mistake of fact. The Authority contested this decision, arguing that the mistake was one of law, not fact, and thus should not have led to an acquittal.

The primary legal issue before the court was whether Barwick's belief about the speed limit constituted a mistake of fact or a mistake of law. If it was a mistake of fact, Barwick should be acquitted. However, if it was a mistake of law, the acquittal would be improper. The court needed to determine the nature of Barwick's mistake to resolve this issue. The court considered whether the speed limit signs were clear and if Barwick had any reasonable grounds to believe the speed limit was different from what was legally applicable. The court also examined whether a driver’s misunderstanding of a speed limit sign could negate their obligation to know the correct speed limit.

In delivering its judgment, the court held that Barwick's belief about the speed limit was a mistake of law, not fact. The court found that drivers are expected to know the speed limits for roads they travel on, regardless of any misleading signs. The court emphasised that a driver cannot rely on their personal belief about speed limits if it contradicts the legal speed limit. Given that Barwick's mistake did not stem from an honest misunderstanding of a factual circumstance, but rather a disregard for the legal speed limit, the court ruled that the local court should not have acquitted Barwick. The appeal was thus allowed, and the matter was remitted to the local court for re-sentencing on the speeding charges.