Palestine Action ban undermined confidence in anti-terror laws, Supreme Court told

The banning of Palestine Action has led to a "crisis in confidence" in the UK's anti-terrorism laws and triggered unprecedented civil disobedience from law-abiding protesters, the Supreme Court has been told.

Opening a major legal challenge to the group's proscription last year, lawyers for co-founder Huda Ammori said that no other protest organisation had been treated the same way.

They told the five justices that the UK's highest court had never before had to consider whether banning a group under terrorism legislation was compatible with freedom of speech and protest.

Twenty-seven protesters were arrested outside the Supreme Court on Wednesday as the hearing took place, the Metropolitan Police said.

Lawyers for Ammori told the court that thousands of elderly people, many veterans of other radical causes, had been arrested for holding up signs supportive of the group since its proscription.

Home Office figures seen by the BBC indicate that there have been more than 4,000 arrests so far at protests in which people have held up signs supportive of the group.

In practice, many demonstrators have been arrested more than once, with 1,200 charges authorised by prosecutors to date. Those trials are in limbo until the outcome of this case.

Henry Blaxland KC told the court that "far from depriving Palestine Action of the oxygen of publicity" and "far from discrediting its brand", proscription of the group has had the opposite effect.

"All it's done is to pour fuel on to a fire of one of the most publicly-contested issues of our time," he said.

"It was disproportionate to do that and in my submission completely unnecessary."

During often tense exchanges with the judges, Ammori's team accepted that Palestine Action could not be described as an ordinary and peaceful protest group.

They said that its members had carried out "direct action" protests by occupying or vandalising firms linked to Israel's military - with only three of 385 incidents assessed by the Home Secretary as constituting an offence under the Terrorism Act.

The UK's definition of terrorism includes incidents of serious damage to property for a cause - and at least two break-ins at defence firms have been described in criminal courts as having caused millions in damage.

Raza Husain KC, for Ammori, said that the judges had to put aside allegations of criminality - for which the state had many powers - and consider whether the Home Secretary's decision to label the group as terrorists had been disproportionate.

"Palestine Action was proscribed on the basis of less than one per cent of its actions over five years assessed as falling within the outer limits of a definition of terrorism," he said.

"The Home Secretary's own experts confirmed the vast majority of its direct action would not constitute an act of terrorism on the basis that any damage to property is typically more minor. Common tactics include graffiti, petty vandalism, occupation, and lock-ons."

One Palestine Action member has been convicted and jailed of fracturing a police officer's back with a sledgehammer - but the court was told that the group had never advocated such violence.