Secondary legislation which significant lowered the threshold on protest crackdowns to anything that caused “more than minor” disruption was beyond what was allowed by the Police, Crime, Sentencing and Courts Act 2022, judges said.

The court’s ruling that the legislation should be quashed has been suspended pending an appeal.

Human rights organisation Liberty, which brought the challenge, has called on the police to refrain from using these powers until the appeal has been heard and for prosecutions under the law to be put on hold pending the appeal.

It says hundreds of protesters have been arrested under these measures since they were created, including the climate activist Greta Thunberg who was acquitted of all charges in a hearing in February 2024.

Akiko Hart, Liberty’s director, said: “This ruling is a huge victory for democracy, and sets down an important marker to show that the government cannot step outside of the law to do whatever it wants.

“We all have the right to speak out on the issues we believe in, and it’s vital that the government respects that.

“These dangerous powers were rejected by Parliament yet still sneaked through the back door with the clear intention of stopping protesters that the government did not personally agree with, and were so vaguely worded that it meant that the police were given almost unlimited powers to shut down any other protest too.

“This judgment sends a clear message that accountability matters, and that those in power must make decisions that respect our rights.”

Katy Watts, lawyer at Liberty, added: “We launched this legal action to ensure that the government was not allowed to wilfully ignore the rules at the expense of our fundamental human rights.

“It is not up to the government to decide what causes people can protest on, nor is it right for the government to sideline both Parliament and the public in making these decisions. Those in power cannot just cherry pick who they consult in order to get the results they want.

“In recent years, the government has introduced a whole host of new laws which have tried to stop people from being able to speak up for what they believe in. Powers in the Policing Act and Public Order Act have criminalised the fundamental ways of protest, such as for being too noisy.

“It is worrying that the government is still planning to bring in more restrictions, including a ban on wearing face coverings at protests, which would make it unsafe for some disabled people and political dissidents from Hong Kong to protest.

“We hope today’s ruling makes the government take stock, and that they instead work to protect our rights rather than strip them away further.”