Controversial laws to restrict protests in New South Wales following the Bondi Beach terrorist attack have been struck down by the state's top court.

The Court of Appeal accepted arguments by protest groups that the expanded police powers were unconstitutional, in a judgment handed down on Thursday afternoon.

The laws were ruled to have "impermissibly burdened" the implied right to freedom of political communication under Australia's constitution in a joint judgment by Chief Justice Andrew Bell, Justice Julie Ward and Justice Stephen Free.

There were hushed cheers and hugs inside the Banco Court in Sydney, the state's largest, as supporters draped in keffiyeh scarves watched on.

The plaintiffs, Elizabeth Jarrett of the Blak Caucus, Joshua Lees of the Palestine Action Group, and Michelle Berkon from Jews against the Occupation '48, launched the challenge in early January.

Mr Lees called on Mr Minns to resign, saying he has been warned by MPs and legal experts the laws were unconstitutional.