ONE woman is dressed provocatively in a black bra. Another sports red high heels and stockings. Their long-haired male companions are dressed in scruffy blue boiler suits and the occasional riot helmet.

The costumes may look harmless, but for the Space Hijackers — a small group of part-time anarchists with a penchant for street entertainment — they have been enough to earn them charges of impersonating police officers.

The group was pictured en route to last April’s G20 protests surrounding a dilapidated personnel carrier, complete with fake plastic machinegun and speakers blaring out the Ride of the Valkyries. Their jaunt now forms the cornerstone of one of the most bizarre prosecutions mounted in a British court in recent years.

In what critics say is a misjudged effort to justify police tactics at the protests, Keir Starmer, the director of public prosecutions, brushed aside objections and decided last month that 11 of the Space Hijackers would face a four-day trial at a magistrates’ court in February.

The motley group of students and young professionals is not accused of attacking police or smashing windows.Instead, its members face a charge normally reserved for criminals who con their way into the homes of elderly people by wearing full police uniform and producing a fake warrant card.

The case has so far cost the taxpayer tens of thousands of pounds and occupied detectives and prosecutors for hundred of hours.

MPs, senior legal experts and the group’s lawyers this weekend said the prosecution should be withdrawn. Many believe it is likely to backfire and heap further embarrassment on the Metropolitan police, already facing criticism over its heavy-handedness during the protests, which left one man dead and prompted a review of anti-riot tactics.

Ian Tomlinson, a 47-year-old newspaper vendor, died after he was shoved to the ground. A police officer is facing investigation for possible manslaughter.

The impersonation case comprises nearly half the 27 prosecutions ordered since the G20 protests, which were attended by tens of thousands of demonstrators.

Apart from the Space Hijackers case, the police and Crown Prosecution Service have proceeded with only a handful of charges of violent disorder and criminal damage.

Keith Vaz, the chairman of the Commons home affairs select committee, which carried out an inquiry into the riots, questions the entire prosecution of the Space Hijackers.

“The G20 protests resulted in some very serious incidents for those who were being policed and those who were policing,” he said. “But I’m extremely surprised that there are going to be prosecutions that do not meet the very important test of whether a prosecution is in the public interest.”

Leah Borromeo, 30, a freelance writer who was arrested wearing a black bra and boiler suit, is one of the defendants. She said the case seemed to be a “box-ticking exercise” so that prosecutors could show they were taking action against a “quota” of people.

“If I’m guilty of anything it’s of impersonating a stripper, not a police officer,” she said. “I don’t like being criminalised, because I have done nothing wrong.”

Critical to the case will be evidence that none of the dozens of witnesses being brought by the defendants believed they were police officers.

Raj Chada, their lawyer, said the prosecution needed to prove the 11 intended to deceive others into believing they were police.

“Far from pretending to be police officers they were protesting in a way that was both peaceful and designed to be entertaining,” said Chada. “The protests were on April Fool’s Day and this prosecution is like an April Fool’s joke.

“There were serious issues at the G20 protests. So why were the police devoting serious time and resources to arresting and then prosecuting these people? It’s absolutely ridiculous.”

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