The appellant was charged under a Calgary municipal by-law for being on a street for the purpose of prostitution.
She challenged the constitutional validity of the by-law, arguing it invaded the federal government's exclusive jurisdiction over criminal law.
The Supreme Court of Canada held that the by-law was ultra vires the province and the municipality, as its pith and substance was an attempt to control or punish prostitution rather than to regulate street use or public nuisance.
The appeal was allowed and the acquittal restored.
