A protest outside Sydney Town Hall that ended with arrests and a blocked march is now facing a legal unwind – after the police powers used to control the gathering were found to be invalid in court.

NSW Police Commissioner Mal Lanyon said on ABC Radio on Wednesday morning that charges linked to the Public Assembly Restriction Declaration (PARD) are under review.

“Pending a review, police would drop charges laid under the public assembly restriction declaration law,” Ms Lanyon said.

The February demonstration in central Sydney, held in protest against the visit of the Israeli president to Australia, saw police move to prevent a planned march during a major public gathering outside Sydney Town Hall.

Officers blocked participants from progressing along the proposed route and dispersed parts of the crowd, with multiple arrests made on the night and later charges laid over alleged breaches of police directions and other offences.

It remains unclear how many of the 29 additional protesters charged after the rally will be affected by the review, with a range of allegations still before the courts, including assaulting police, offensive behaviour and throwing objects.

Some lawyers have also raised questions over whether directions issued during the operation, including alleged breaches of police instructions, fall within the scope of the invalidated framework.

The PARD declaration was used at the time of the protest with police citing it as the basis for stopping the march from proceeding.

Last month, the Court of Appeal ruled the legislation unconstitutional after a challenge by the Palestine Action Group and Blak Caucus, finding it unlawfully extended police powers to restrict public gatherings for 90 days following a terrorist attack.

The laws were introduced after the Bondi Beach terror attack in December, where 15 people were killed and more than 40 injured when two gunmen opened fire during a Hanukkah celebration.

Premier Chris Minns previously argued that charges from the Town Hall protest could still stand under a separate major events declaration in force during the visit, typically used for large-scale sporting or entertainment events.

The Palestine Action Group has since indicated it may challenge the validity of that framework as well, arguing it was also used to restrict the protest.

Greens MP and solicitor Sue Higginson said the Commissioner’s comments confirmed the legal foundation for some arrests had collapsed.

“The Police Commissioner has now confirmed that people were charged under laws that were unconstitutional and invalid. Those charges should never have been laid,” Ms Higginson said.

“These unlawful laws empowered police to violently crack down on a peaceful community protest at Town Hall.

“People were wrongfully arrested and brutally assaulted because the Minns Labor Government chose to impose unconstitutional anti-protest laws on the people of NSW.

“All charges against every person charged that night at Town Hall should now be dropped. The entire police operation was built around unlawful restrictions that had no legal force,” she said.

The Human Rights Law Centre also weighed in following last month’s court decision, calling for charges to be dropped and for the state to overhaul its protest laws after the ruling found the restrictions unlawfully burdened political communication and were beyond constitutional power.

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