This has got to stop. Britain's snooper state is getting completely out of hand. We are sleepwalking into a surveillance society, and we must wake up. When the Stasi started spying on me, as I moved around East Germany 30 years ago, I travelled on the assumption that I was coming from one of the freest countries in the world to one of the least free. I don't think I was wrong then, but I would certainly be wrong now. Today, the people of East Germany are much less spied upon than the people of Britain. The human rights group Privacy International rates Britain as an "endemic surveillance society", along with China and Russia, whereas Germany scores much better.

An official report by Britain's interception of communications commissioner has just revealed that nearly 800 public bodies are between them making an average of nearly 1,000 requests a day for "communications data", including actual phone taps, mobile phone records, email or web search histories, not to mention old-fashioned snail mail. The Home Office website notes that all communication service providers "may be served with a notice by the secretary of state requiring them to maintain a permanent intercept capability. In practice, agreement is always reached by consultation and negotiation." How reassuring.

The fantastic advance of information and communications technology gives the state - and private companies as well - technical possibilities of which the Stasi could only dream. Most of your life is now mapped electronically, minute by minute, centimetre by centimetre, through your mobile phone calls, your emails, your web searches, your credit card purchases, your involuntary appearances on CCTV, and so on. Had the East German secret police had these snooping super-tools, my Stasi file would have measured at least 3,000 pages, not a mere 325.

We therefore need to strengthen the protection of data, privacy and civil rights simply to remain as free as we were before. As technology lifts the sea level of information flow, we have to build up the dykes. To a limited extent, this has been happening; some legal data protection safeguards have been improved. Our stalwart information commissioner, Richard Thomas, has fought a valiant battle to protect what the Germans call, with portentous profundity, the right to informational self-determination. A valiant battle, but a losing one - as the commissioner himself acknowledges. The warning that we are "sleepwalking into a surveillance society" comes from him.

For even as he tries to strengthen the dykes, more powerful arms of government are busy tearing them down: in the name of fighting terrorism, crime, fraud, child molestation, drugs, religious extremism, racial abuse, tax evasion, speeding, illegal parking, fly-tipping, leaving too many garbage bags outside your home, and any other "risk" that any of those nearly 800 public (busy)bodies feels called upon to "protect" us from. Well, thank you, nanny - but kindly eff off to East Germany. I'd rather stay a bit more free, even if means being a bit less safe.

Yes, I recognise that the threat from homegrown suicide bombers - like those who struck London on July 7 2005, and extremists who have been picked up since, including the recently convicted would-be beheader of a British soldier - is particularly difficult to detect. I accept that it requires some extra surveillance and prevention powers. The balance between security and liberty needs to be recalibrated. But in the last decade the British government has erred too far on the side of what is alleged to be increased security.

An over-mighty executive, authoritarian busybody instincts at all levels of government, a political culture of "commonsense" bureaucratic judgments, rather than codified rights protected by supreme courts and, until recently, a gung-ho press forever calling for "something to be done": this fateful combination has made Britain a dark outrider among liberal democracies.

The birthplace of laissez-faire liberalism has morphed into the database state. We have more CCTV cameras than anyone. We have the largest DNA database anywhere. Plans are far advanced to centralise all our medical records and introduce the most elaborate biometric ID cards in the world. All this from a government which, having collected so much data on us, goes around losing it like a late-night drunk spreading the contents of his pockets down the street. Twenty-five million people's details mislaid by Her Majesty's Revenue and Customs; at least 100,000 more on an awol Royal Navy laptop; and so it goes on.

Meanwhile, the government has just laid before parliament its latest counter-terrorism bill. Besides the notorious proposal to increase the period of detention without charge to 42 days, this includes provisions that, as the attached official notes explain, allow anyone to give information to the intelligence services "regardless of any duty to keep the information private or of any other restriction" (other than those mentioned in a pair of elastic subclauses). Such information can then be shared or disclosed by that service more or less at will.

This will not do; and even the staunchest supporters of the smack of firm government are beginning to say as much. The Daily Mail, that prince of firm-smackers, yesterday ran a leading article which concluded that "Under this government - of whom the Stasi would have been proud - the balance between state power and individual liberty has been outrageously skewed. It must be restored." This is something on which press and politicians of left and right are beginning to agree.

Of course that flourish about the Stasi is hyperbole. As someone who actually lived under the Stasi, I know we're nowhere near that. But the amount of information collected and shared - not to mention lost - by the British government far exceeds the Stasi's modest 160km of paper files. The potential for it to be abused, in the wrong hands, is simply enormous. Liberty is not preserved simply by putting our trust in the good intentions of our rulers, civil servants and spooks. The road to hell is paved with good intentions.

My sense is that the tide is just beginning to turn in British public, published and parliamentary opinion. I hope the Liberal Democrats, Conservatives, Labour backbenchers and the House of Lords will between them give the new bill the roasting it deserves. Some of our watchdog commissioners and more independent-minded judges are already sounding the alarm. If the government were still to be so foolish as to try to introduce the new ID cards before the next election, it could be to Gordon Brown what the poll tax was to Margaret Thatcher. Comprehensive, compulsory ID cards would directly impinge on every single citizen; this is just the kind of thing the British like to get bloody-minded about.

The Liberal Democrat leader Nick Clegg has said he would go to jail rather than accept an ID card of this intrusive kind. So would I. And so, I believe, would many thousands of our fellow-citizens. (There's a good website called NO2ID where you can join the fray.) Which is why, I suspect, the government won't be so foolish. But we need to draw the line well before ID cards. There are liberties that we have already given away, while sleeping, and we must claim them back.

www.timothygartonash.com