Twenty people pre-emptively arrested before last year's Royal wedding had their claim that the Metropolitan Police acted unlawfully thrown out at the High Court in London today.
The Met were accused of effectively "suppressing anti-monarchist sentiment" when they carried out the searches and arrests last April.
But the court ruled that the police had acted within their powers and were not guilty of operating an unlawful policy.
Lord Justice Richards and Mr Justice Openshaw, presiding, dismissed applications for judicial review from 20 individuals among scores arrested or subjected to searches before or on the wedding day.
They declared: "We find nothing in the various strands of the claimants' case, whether taken individually or cumulatively, to make good the contention that the policing of the royal wedding involved an unlawful policy or practice, with an impermissibly low threshold of tolerance for public protests."
Human rights activists say the case has major implications for the policing of other major events, including the Olympics.
Karon Monaghan QC, appearing for the bulk of those detained, had argued at a previous hearing that her clients had all been pre-emptively arrested under an unlawful policy to prevent disruption to the wedding.
She argued that the case touched on "the most important of constitutional rights, namely the right to free expression and to protest, both of which are elemental to a properly functioning democracy."
Among the claimants were 15 individuals arrested at locations across London.
One of the 15 was Brian Hicks, 44, a republican with previous convictions for minor offences dating back to his youth, but nothing for over 20 years.
Another claimant, a 16-year-old youth referred to as "M" was arrested and detained for nine hours before being released without charge.
He also had his DNA, fingerprints and photograph taken which the police subsequently refused to destroy.
A further two claimants Hannah Pearce and Shirin Golsirat, squatters in Camberwell Road, challenged the lawfulness of searches made contending that while warrants authorised searches for stolen bicycles, bike parts and computers - the real purpose was to prevent disruption to the wedding.
But, in a lengthy judgement running to 270 paragraphs, the judges dismissed all claims of human rights and statutory violations by the police.
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