Protesters seek judicial review of Met's actions in case that could have implications for way jubilee and Olympics are policed

Activists who were rounded up before last year's royal wedding are challenging the Metropolitan police in the high court on Monday in a case that could have implications for the way the Queen's diamond jubilee celebrations and the Olympics are policed.

Scores of people were arrested and many more detained before the wedding of Prince William and Kate Middleton last April, leading to claims that police were unlawfully criminalising legitimate protests before they had taken place.

Lawyers acting on behalf of 20 of those involved are seeking a judicial review of the police action at the high court.

Sophie Priestley, of Tuckers Solicitors, is representing two environmental campaigners who were detained at what police described as an "environmental training camp" near Heathrow, the day before the wedding.

She said: "It appears that the police were determined to restrict or remove the sight of protest from central London during the royal wedding. With the Queen's jubilee celebrations and the Olympics approaching it should not be forgotten that the real strength of our heritage and tradition lies not in the spectacle and pageantry of events like these, but rather in the rich history of our hard-won democratic freedoms."

In the months leading up to the wedding, a series of demonstrations by students, trade unionists and others saw hundreds of thousands of people take to the streets to protest against government cuts. There were outbreaks of disorder and in one case student demonstrators attacked a car carrying Prince Charles and his wife Camilla.

Senior police chiefs said at the time they were planning to take pre-emptive action to ensure there was no repeat of the trouble.

Lynne Owens, then assistant commissioner at the Met, told journalists: "We have both overt and covert policing activities on going and we will prevent people coming to London to cause criminal behaviour if that is their intention."

The police raided several squats and activist camps in the days before the wedding and stopped other protesters on the morning of the event.

Sophie Naftalin, of Bhatt Murphy solicitors, is representing 15 protesters who were pre-emptively arrested on the day of the wedding. They were all detained until after the wedding celebrations but no further action was taken against them.

"This matter touches upon the most important of constitutional rights – namely the right to free expression – which is fundamental to any properly functioning democracy," she said. "While our clients recognise the difficulties of policing large-scale operations, it is nevertheless clear that the police must strike the right balance between maintaining public order and allowing people to express their political beliefs."

Two of those taking action in court on Monday were detained at Sipson environmental camp near Heathrow and say they had no intention of protesting. Police claimed the camp was occupied by "extreme leftwing or environmental groups" and claimed there was evidence to suggest paint bombs were being made at the site. No paint bombs were found and lawyers say police had no evidence of any link between the camp and any royal wedding protests. All those detained were later released without charge.

Theodora Middleton, one of the activists, said: "We simply cannot have a situation where the police are allowed to break into people's homes without any evidence that a crime has been committed. This kind of harassment, based it seems on crude political profiling, is entirely inappropriate in a democratic society." Daniel Randall, who was detained near Trafalgar Square on the day of the demonstration, said: "This was a very explicit manoeuvre by the state to prevent people raising dissenting voices."

Another of the protesters, Hannah Eiseman, said: "It seemed like they had their script and once we were on the wrong end of that, we were being treated like criminals… any possible dissent was being cleared and human rights were being suspended briefly to make way for pageantry. Pageantry is all well and good, but human rights are way more important."