Last weekend, some friends and I took a trip to the seaside. We ate ice-cream on the beach in the brilliant sun, and tiptoed out into the icy waves, negotiating bits of floating plastic, shrieking like excited children with rolled-up trousers and tucked-in skirts: five get messy in Brighton. It was, in every respect, a normal holiday. Except for the eight or nine uniformed police officers watching us paddle.

Two "forward intelligence teams" had been sent down from London specifically to keep an eye on us, taking pictures as we handed out flyers about tax avoidance with a local anti-cuts group and ate chips with little wooden forks. If this really represents a danger to the state, the state is in far more trouble than we have been led to believe.

Bad things happen to people who protest against the British government and its austerity program. You no longer even have to have committed a crime to be reported to the police. This week, the City of Westminster's "Counter Terrorist Focus Desk" issued a call for all "anarchists" to be identified, stating that anyone who thinks that the state is "undesirable, unnecessary and harmful" should be considered as dangerous as al-Quaeda. Presumably the architects of the "big society" project will soon be getting the heavy knock at the door.

The Metropolitan Police have made their priorities extremely clear. Up to 200 officers have been devoted to hunting down students and anti-cuts activists, knocking on the doors of school pupils and arresting them for their part in demonstrations against education cutbacks that took place nine months ago. Thirty UK Uncut protesters are still facing charges for their part in a peaceful demonstration in Fortnum and Mason, footage from the police recordings of which shows some dangerous anarchists waving placards in the foyer and batting a beach ball over a stack of expensive cheese. Up to 300 activists have been arrested so far, in a joint operation that has already cost the taxpayer £3.65m. By contrast, only eight man-hours were spent in 2009 investigating the allegation that feral press barons were being permitted to run what amounted to a protection racket at the Met.

When he resigned as Police Commissioner, Sir Paul Stephenson listed some of his proudest moments at the Met. These included the force at their "glorious and unobtrusive best" on the occasion of the royal wedding. Thats not how I remember it. I remember hippies and students all over the country being dragged out of their homes and arrested for crimes they hadnt even thought of committing. The disgraced former police chief also congratulated the force on their "professional and restrained approach" at the recent student demonstrations. Thats not what I saw. I saw them dragging Jody McIntyre out of his wheelchair. I saw crowds of students and schoolchildren screaming and scrambling over one another as they fled a charge by mounted police that put at least forty-three of them in hospital and left one young man fighting for his life on the operating table.

As students and activists continue to be charged with violent disorder, it seems to have been forgotten that this offence normally relates to acts of self-defence in the face of police brutality. It is now a crime to fight back when you're getting bludgeoned with batons for daring to take a stand against unfair, unnecessary cuts to public services. Police officers, meanwhile, are rarely charged in connection with violence against protesters. In 2009, despite video evidence showing Sgt Delroy Smellie assaulting Nicola Fisher, District Judge Daphne Wickham ruled that he had acted lawfully. This week, the same judge ignored sentencing guidelines to send Jonnie Marbles to prison for attempting to splatter Rupert Murdoch with shaving foam.

Marbles hurt nobody with his misguided prank. Nor did 20-year-old Frank Fernie, who is serving a year in jail for "throwing two sticks at police officers" in full body armour. Nor did Charlie Gilmour, whose drunken antics at the student demonstrations earned him 16 months in Wandsworth, where he is currently spending 23-hours a day locked in a tiny cell with an armed robber. Although some have identified these opprobrious sentences as attacks on the right to protest, the courts seem only to be making examples of certain types of protester whose principles directly threaten the ruling consensus. Stephen Lennon, the leader of the far-right English Defence League, was recently convicted of leading a street brawl and threatening members of the public, but received only a fine and a community order.

The Home Office has admitted to ongoing discussions with the Metropolitan police about operational policies and procedures concerning UK Uncut and other anti-cuts groups. So much for the separation of powers. So much for the rule of law. I am sick of it. I am sick of seeing peaceful protesters scapegoated as violent thugs and sent to prison while right-wing extremists and corrupt media tycoons walk free. At a time when millions have urgent and legitimate grievances with this government, the criminalisation of dissent should outrage us all.