A court in Sydney has struck down a controversial state law that made it illegal to "annoy" pilgrims gathered for a Roman Catholic youth festival.
The ruling came as the World Youth Day festival opens. It will be attended by Pope Benedict XVI later this week.
The challenge to the law was brought by a coalition of protest groups.
Activists say they plan to hold a rally on Saturday at which they will demonstrate against the Church's stand on homosexuality and birth control, by handing out condoms and wearing provocative T-shirts.
Civil liberty groups had denounced the New South Wales state law - which threatened fines of up to A$5,500 (£2,680) against anyone causing "annoyance" to pilgrims - as unnecessary and repugnant.
The Sydney Morning Herald today:
Annoyance clause invalid
The judges said that the interpretation of clause 7.1 of the act, which allowed regulation of conduct deemed to be a cause of "annoyance", was invalid because it "affects freedom of speech in a way that, in our opinion, is not supported by the statutory powers".
There was "no intelligible boundary" on what "causes annoyance".
The regulation relating to annoyance "could be expected to have a chilling effect upon the exercise of their freedom of speech because of the very uncertainty about the degree of its infringement upon that freedom", they said.
Well done Ms. Evans. I hope you stand for election again in the future.
Australia needs its fighters.