Is Murdoch now finished in the UK? As the pursuit of Gordon Brown by the Sunday Times and the Sun blows the hacking scandal into new corners of the old man's empire, this story begins to feel like the crumbling of the Berlin Wall. The naked attempt to destroy Brown by any means, including hacking the medical files of his sick baby son, means that there is no obvious limit to the story's ramifications.

Illustration by Daniel Pudles

The scandal radically changes public perceptions of how politics works, the danger corporate power presents to democracy, and the extent to which it has compromised and corrupted the Metropolitan police, who have now been dragged in so deep they are beginning to look like Murdoch's private army. It has electrified a dozy parliament and subjected the least accountable and most corrupt profession in Britain – journalism – to belated public scrutiny.

The cracks are appearing in the most unexpected places. Look at the remarkable admission by the rightwing columnist Janet Daley in this week's Sunday Telegraph. "British political journalism is basically a club to which politicians and journalists both belong," she wrote. "It is this familiarity, this intimacy, this set of shared assumptions … which is the real corruptor of political life. The self-limiting spectrum of what can and cannot be said … the self-reinforcing cowardice which takes for granted that certain vested interests are too powerful to be worth confronting. All of these things are constant dangers in the political life of any democracy."

Most national journalists are embedded, immersed in the society, beliefs and culture of the people they are meant to hold to account. They are fascinated by power struggles among the elite but have little interest in the conflict between the elite and those they dominate. They celebrate those with agency and ignore those without.

But this is just part of the problem. Daley stopped short of naming the most persuasive force: the interests of the owner and the corporate class to which he belongs. The proprietor appoints editors in his own image – who impress their views on their staff. Murdoch's editors, like those who work for the other proprietors, insist that they think and act independently.

It's a lie exposed by the concurrence of their views (did all 247 News Corp editors just happen to support the invasion of Iraq?), and blown out of the water by Andrew Neil's explosive testimony in 2008 before the Lords select committee on communications.

The papers cannot announce that their purpose is to ventriloquise the concerns of multimillionaires; they must present themselves as the voice of the people. The Sun, the Mail and the Express claim to represent the interests of the working man and woman. These interests turn out to be identical to those of the men who own the papers.

So the rightwing papers run endless exposures of benefit cheats, yet say scarcely a word about the corporate tax cheats. They savage the trade unions and excoriate the BBC. They lambast the regulations that restrain corporate power. They school us in the extrinsic values – the worship of power, money, image and fame – which advertisers love but which make this a shallower, more selfish country. Most of them deceive their readers about the causes of climate change. These are not the obsessions of working people. They are the obsessions thrust upon them by the multimillionaires who own these papers.

The corporate media is a gigantic astroturfing operation: a fake grassroots crusade serving elite interests. In this respect the media companies resemble the Tea Party movement, which claims to be a spontaneous rising of blue-collar Americans against the elite but was founded with the help of the billionaire Koch brothers and promoted by Murdoch's Fox News.

Journalism's primary purpose is to hold power to account. This purpose has been perfectly inverted. Columnists and bloggers are employed as the enforcers of corporate power, denouncing people who criticise its interests, stamping on new ideas, bullying the powerless. The press barons allowed governments occasionally to promote the interests of the poor, but never to hamper the interests of the rich. They also sought to discipline the rest of the media. The BBC, over the last 30 years, became a shadow of the gutsy broadcaster it was, and now treats big business with cringing deference. Every morning at 6.15, the Today programme's business report grants executives the kind of unchallenged access otherwise reserved for God on Thought for the Day. The rest of the programme seeks out controversy and sets up discussions between opponents, but these people are not confronted by their critics.

So what can be done? Because of the peculiar threat they present to democracy there's a case to be made for breaking up all majority interests in media companies, and for a board of governors, appointed perhaps by Commons committee, to act as a counterweight to the shareholders' business interests.

But even if that's a workable idea, it's a long way off. For now, the best hope might be to mobilise readers to demand that journalists answer to them, not just their proprietors. One means of doing this is to lobby journalists to commit themselves to a kind of Hippocratic oath. Here's a rough stab at a first draft. I hope others can improve it. Ideally, I'd like to see the National Union of Journalists building on it and encouraging its members to sign.

'Our primary task is to hold power to account. We will prioritise those stories and issues which expose the interests of power. We will be wary of the relationships we form with the rich and powerful, and ensure that we don't become embedded in their society. We will not curry favour with politicians, businesses or other dominant groups by withholding scrutiny of their affairs, or twisting a story to suit their interests.

"We will stand up to the interests of the businesses we work for, and the advertisers which fund them. We will never take money for promulgating a particular opinion, and we will resist attempts to oblige us to adopt one.

"We will recognise and understand the power we wield and how it originates. We will challenge ourselves and our perception of the world as much as we challenge other people. When we turn out to be wrong, we will say so."

I accept that this doesn't directly address the power relations that govern the papers. But it might help journalists to assert a measure of independence, and readers to hold them to it. Just as voters should lobby their MPs to represent them and not just the whips, readers should seek to drag journalists away from the demands of their editors. The oath is one possible tool that could enhance reader power.

If you don't like it, suggest a better idea. Something has to change: never again should a half a dozen oligarchs be allowed to dominate and corrupt the life of this country.

• A fully referenced version of this article can be found on George Monbiot's website. On Twitter, @georgemonbiot.