Police arrested 27 protesters outside the Supreme Court on Wednesday as justices heard an appeal against the ban on Palestine Action.
Group co-founder Huda Ammori is taking a legal battle against the Government’s decision to ban the group under anti-terrorism laws to the UK’s highest court in a bid to quash the prohibition.
Demonstrators assembled outside the central London court before the start of the hearing, with police officers seen carrying several people away into nearby vans.
The Metropolitan Police later said 27 people had been arrested on suspicion of displaying support for a proscribed organisation.
Several demonstrators held placards using the same wording as an X post written by the wife of a national security adviser.
Sarah Helm, a journalist and author who is married to Jonathan Powell, posted on X in October: “God help us authors who support Palestine and Palestine Action.”
The protesters inserted different words instead of “authors” on their signs, including “normal people”, “students” and “sons of Holocaust survivors”.
Actor Alfred Enoch held up a sign reading “this is democracy not terrorism” as other demonstrators were removed by police.
Mr Enoch told the Press Association that he hoped the ban on Palestine Action was dropped.
He said: “You can see the chilling effect it’s had.
“I think it’s part of a wider erosion of rights of protest, which is fundamental to a democracy.
“People don’t even feel safe enough to come out and say that.”
During the hearing, Raza Husain KC, for Ms Ammori, told the court that the objectives of Palestine Action “were aligned with, rather than abhorrent to liberal democratic values”.
In written submissions, the barrister said that only three out of 385 actions carried out by Palestine Action over a five-year period were assessed as meeting the definition of terrorism under part of the Terrorism Act.
He continued: “This was solely on the basis that they involved ‘serious damage to property’.
“In other words, the Home Secretary’s advisers assessed that less than 1% of Palestine Action’s direct action protest activities over five years fell within a definition of terrorism.”
Mr Husain said the ban has led to “the total destruction of a protest group which enjoyed widespread support from across civil society”.
Expressing support for the group is now an offence under the Terrorism Act, with the court told more than 3,000 people have been arrested since the ban.
Mr Husain later said that Palestine Action is the first of 98 proscribed organisations to be banned exclusively for causing serious damage to property “with no suggestion that it advocated serious violence against the person”.
The case has come to the Supreme Court after Ms Ammori challenged the then-home secretary Yvette Cooper’s 2025 decision to ban the group at the High Court, with three judges finding in February that it was unlawful.
But five Court of Appeal judges overturned the decision in June, finding the ban was lawful and a “justified and proportionate” interference with freedom of expression rights.
The Home Office, which is opposing the appeal, has said the Court of Appeal made no legal error.
In written submissions Sir James Eadie KC, for the Home Office, said the Court of Appeal had rejected Ms Ammori’s attempt to portray Palestine Action as a “non-violent direct action protest group”.
He later said acts which involved serious damage to property could be considered terrorism and the action did not need to involve violence or an intent to endanger life.
The barrister later said the information given by Ms Ammori about Palestine Action’s “structure, activities and membership” remain “notably vague and incomplete” in her written submissions to the Supreme Court.
Sir James also said that the group’s ban does not prevent public support for Palestine or opposition to Israel and the Israel Defence Forces, and that there are still “vocal large-scale and frequent expressions of support for the pro-Palestinian cause” with only direct support of Palestine Action restricted.
In written submissions on behalf of the Community Security Trust and the Jewish Leadership Council, Adam Wagner KC said the UK Jewish community is “especially vulnerable to Palestine Action’s violent activities” as activists had attacked “Jewish charities and Jewish-owned businesses”.
He said lifting the proscription would “re-arm and revitalise a sinister and dangerous movement” and could serve as a “green light” for perpetrators of “violent antisemitism more broadly”.
The hearing before Lords Reed, Sales, Lloyd-Jones, Briggs and Stephens is due to begin on Wednesday with a decision expected at a later date.
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