Police acted unlawfully when they banned the group’s London protests last month.
A police ban on Extinction Rebellion protests in London has been ruled unlawful by the High Court.
In a judgement delivered on Wednesday morning, it was ruled that police acted unlawfully when a banning order was imposed during the group’s string of protests in the capital last month.
Large areas of London were brought to a standstill when thousands of protesters took part in disruptive action, demanding action at the time.
The Met Police subsequently claimed that the order was necessary to halt disruption, but High Court judges have said they acted unlawfully.
In his judgement, Mr Justice Dingemans said: “Separate gatherings, separated both in time and by many miles, even if coordinated under the umbrella of one body, are not a public assembly within the meaning of … the Act.
“The XR autumn uprising intended to be held from 14 to 19 October was not therefore a public assembly … therefore the decision to impose the condition was unlawful because there was no power to impose it under … the Act.”
The ban, under Section 14 of the Public Order Act, came into force at 9pm on Monday, October 14. It remained in effect until Friday October 18, when than 400 people were arrested.
The High Court decision could potentially open the door to a string of legal challenges from protestors who argue that they were unlawfully detained.
Baroness Jenny Jones, one of several key figures who brought the legal challenge, told The Guardian: “This is an historic win because for the first time we’ve challenged the police on overstepping their powers and we’ve won. It’s great.”
Other key figures who brought the challenge included Caroline Lucas and Ellie Chowns of the Green party, Labour MPs Clive Lewis and David Drew, Labour activist Adam Allnutt and environment writer George Monbiot.
Prior to the warning, Lawyer Tobias Garnett warned that some activists are likely to bring legal cases against the Met.
“It means there are a couple of hundred people whose arrests were maybe unlawful,” he warned.
“That means they might have a cause of false imprisonment.”
During two weeks of protests, thousands of activists descended upon London to demand action on climate change. More than 1,800 people were arrested.