Despite the fact that photographs from the first day of the G20 protests in April 2009 show me astride an armoured personnel carrier in black bra and blue boiler suit with another woman straddling me in red stockings, lipstick and heels, the Crown Prosecution Service has charged me and 10 others with impersonating police officers. We've been charged with two counts under Section 90 of the Police Act 1996 – the greater of which carries with it six months in prison.

The vehicle, owned by anarchist pranksters the Space Hijackers, bore a number of fake CCTV cameras bolted onto its turret, a plastic pipe with holes in it for a gun and a bumper sticker that read "How Do You Like My Driving? 0800 F**K YOU". It blared Wagner's Ride of the Valkyries from a sound system. If you can show me a police force that does all that, I can show you a police force on acid.

"This is ridiculous, they'll never press charges," lawyers who attended to the arrested said on the day. Nearly six months and one court appearance later, the CPS is showing no signs of dropping what will be a four-day trial at the City of Westminster magistrates court in February. Eleven people, witnesses for the defence, witnesses for the prosecution, at least half a dozen legal representatives, the paperwork, the man hours, the expense – to what end? There were 27 prosecutions arising from the G20 protests. The rest include violent disorder, affray and setting fire to things at the Bank of England. The Space Hijackers and their tank sought to satirise the aggression stirred up by police ahead of the protests. Police said they expected violence and were "up for it". It was April Fools' day. And it was apparently the start of the "Summer of Rage".

The case of the rather large Sergeant Delroy Smellie (quiet at the back please), charged with assaulting a rather small protester, Nicola Fisher, by smacking her across the face and whacking her with a baton, is representative of the 250 complaints received by the Independent Police Complaints Commission over police violence at the G20. Sure she was short and shouty, but you swat flies. Not women.

Events surrounding the death of Ian Tomlinson show police to be drunk with the illusion of their own powers. Even members of the Metropolitan Police Authority despair over how things are run. They have criticised police over not taking the issue of wearing ID numbers seriously enough. Apparently disciplining those caught without ID badges was unnecessary because they could fall off or officers could forget to put them on. Smellie was not wearing his numbers when he vented his rage at Fisher. That fuelled public anger over the overt disregard for the accountability that wearing ID badges would give. So since the G20, the Met has spent over £40,000 on force identification numbers for public order officers. A very expensive way of paying lipservice if police chiefs don't consider wearing identification important.

There is a feeling that police chiefs and the CPS – run by director of public prosecutions Keir Starmer (formerly a defence lawyer with a long history of human rights cases) – have lost a sense of perspective. The Space Hijackers have a 10-year history of using comedy and theatre to highlight the hypocrisies and failing of the system. I was accepted as their embedded journalist to get a flavour of their version of protest.

Impersonating a police officer is a criminal offence. Rape is a criminal offence. Would you rather see your tax money go towards prosecuting 11 people up for poking fun at the police, or 11 rapists?