Charges laid under a now defunct law against people who attended a Sydney protest against Isaac Herzog will be dropped, police have confirmed, but it remains unclear how many of the 30 protesters charged the decision affects.

The New South Wales police commissioner, Mal Lanyon, said on ABC Radio on Wednesday morning that, pending a review, police would drop charges laid under the public assembly restriction declaration (Pard) law. That law was in force during the February protest at Sydney’s town hall against the Israeli president’s visit to Australia and was cited by police as the reason a march could not go ahead.

Last month, the court of appeal struck down the Pard law, ruling in favour of the Palestine Action Group and Blak Caucus, and finding giving police the power to restrict all protests for a period of 90 days after a terrorist attack was unconstitutional. The law was introduced after December’s Bondi beach terror attack, in which 15 people were killed and more than 40 injured when two gunmen opened fire on a Jewish celebration of Hanukah at a park.

Lanyon said on Wednesday that police were also investigating if directions given under a separate “major events” declaration, which gave police expanded move on and search powers, were lawful.

The premier, Chris Minns, had said in the wake of the Pard being struck down that because the anti-Herzog protest was also covered by a major events declaration charges would still stand for those who did not comply with police directions.

The 30 protesters charged face various offences that fall outside the Pard or major events declaration, including assault police officer, behave in an offensive manner, and throwing an object. Lawyers have indicated that it is unclear whether charges of failing to comply with a direction fell under the Pard law or not.

In Downing Centre local court on Wednesday, 14 of the protesters had their matter adjourned to make way for the review of the charges laid under the Pard.

Lawyer Osman Samin, who is acting for five of those protesters, told the court: “The Pard has fallen over and that might have consequences for a number of these prosecutions, so I understand the police will be reviewing these matters to determine whether they proceed from this point onwards.”

The police prosecutor then told the court that there were “further reasons” for the review, including “considerations to other challenges in relation to other acts”.

The Palestine Action Group has indicated that it may challenge the constitutional validity of the major events declaration, which was in force for the duration of Herzog’s visit and is typically used for major sporting or music events. A major events declaration may limit civil liability claims against police.

Outside court, Nick Hanna, who is representing four of the protesters and has been calling for all the charges to be withdrawn, said he hoped they would be in due course.

He said it remains unclear what police intend to do for the charges that are not relevant to the Pard, but said attempts to “untangle” who was charged under the Pard was an “artificial exercise”.

“The simple reality is that the police crackdown was, in no small part, due to the police refusing to facilitate the peaceful march from town hall to Parliament House, and that refusal was based almost entirely, if not entirely, on the existence of that part,” Hanna said.

The full bench in the court of appeal found in its ruling on the Pard that restricting all protests in order to protect social cohesion was not a “constitutionally legitimate purpose”.

Legal experts have said the landmark judgment could have far-reaching consequences by limiting future attempts by the government to control speech and protests on the basis of “social cohesion”.