The move to widen the UK genetic database is yet another example of a relentless desire to monitor every aspect of our everyday lives

An elderly lady called a BBC Wales radio phone-in programme on which I was a guest last week to say that she wouldn't mind in the slightest if she was stopped and ordered to submit to a DNA test when her dog fouled the pavement. 'Everyone should give their DNA to the police,' she said before the discussion was cut short.

There wasn't time to talk about the sinister absurdity of sanctioning a law that compels old ladies to offer up a mouth swab, whether they want to or not. No time to state that the Home Office and police are engaged on a programme to introduce mass DNA testing by stealth. No time to wonder at the complete absence of parliamentary debate on this crucial issue of liberty. No time to ask whether we can truly trust the police; or to consider what the relatively new science of genetics may be used for in the future; or to wonder at the alarming disappearance of the liberal reflex in British political life.

The show ended and we were on to the news and traffic updates. People were more worried about a lorry blocking the M4. There were supermarkets to visit, jobs to be done, planes to be caught. But before we all shut up shop for the holidays, it is worth underlining one sentence that needs to be written in neon across every town centre: Britain is on the way to becoming a police state.

Writing about the crisis of liberty in Britain, I have been careful not to use these words, but today I see no other conclusion to draw. Taken in the context of the ID card database, the national surveillance of vehicles and retention of information about every individual motorway journey, the huge number of new criminal offences, the half million intercepts of private communications every year, the proposed measures to take 53 pieces of information from everyone wishing to go abroad, which will include powers to prevent travel, this widening of the DNA database for minor misdemeanours confirms the pattern of attack on us all. It is time to pay attention to what the government under Labour has done to British society and what may be awaiting us just a short distance down the road.

Some will say I am being alarmist, but they should consider what we have lost since the mid-Nineties. The inventory of freedoms is eroded every week with measures and laws that individually seem just about acceptable but which accrue to alter the nature of a society where rights and liberty were believed to be as natural as summer rain. People might be reassured by Gordon Brown's talk of a constitutional settlement and a new Bill of Rights, but they should look at his statist views and what is happening in the Home Office, surely one of the most incompetent of the ministries, yet, with its vision for a totally controlled society, also one of the most malign?

Our liberal society is threatened because we don't think it is. This crisis is a crisis because we have not yet acknowledged it.

Let me explain why extension of the database should worry us all. The taking of a swab from a person's mouth - by force when necessary - and retaining that sample indefinitely, whether that person has committed a crime or not, is a very serious intrusion. The state owns and has access to the essence of that individual's being. In the future, it may share the information with whom it likes, investigate the as yet unknown secrets of that sample and make deductions which are prejudicial to that individual or the individual's blood relations. Once on the DNA database, a person is regarded as being in a pool of potential criminals and in an oblique way likely to be guilty of something or other.

DNA is a very useful tool in solving serious crime, but to force people to give a sample because they are not wearing a seatbelt, have littered or let their dog foul a pavement is wrong because it is a measure designed to increase the database, driven by a bureaucratic rather than judicial imperative. In the words of Alex Marshall, deputy chief constable of Thames Valley Police: 'Extending the taking of samples to all offences may be perceived as indicative of the increasing criminalisation of the generally law-abiding citizen.

That is exactly right. Any democratic society with a respect for rights must strike a balance between the needs of crime detection and the principle that a person's privacy is inviolate and their basic innocence unaffected even when they have committed a minor misdemeanour. To compel the sampling of DNA from someone who has driven past a stop sign is a greater offence to society than driving past the stop sign.

The cynical minds of the Home Office concede that the DNA database is inadequate - that the proportion of young black men represented is unacceptable, that the presence of 90,000 innocent minors is regrettable. They argue that these 'anomalies' would disappear if everyone was on the database and DNA was taken at birth as matter of routine. Very well, let the matter of a compulsory national DNA database come before Parliament. Better still, let it become the subject of a referendum so that each party takes a clear stand one way or the other. This is a very important issue which we are letting slip from our grasp. It surely won't be long before someone at the Home Office suggests a DNA sample is added to the information on the ID card database. Indeed, I would guess that is already part of their long-term planning.

Overall, our concern must be that we are allowing the state to accumulate too much power over the individual. The more that power is concentrated, the more likely it is to be abused. On the morning that the Home Office announced the proposals for extending the database, two police officers in Nottingham were found guilty of leaking intelligence to a gangster named Colin Gunn and in London the Independent Police Complaints Commission found that Assistant Commissioner Andy Hayman had misled the public about the shooting of Jean Charles de Menezes.

These cases underline that police officers are not beyond unlawful or irregular behaviour. If DNA evidence was available during the 1974 Birmingham or Guildford bombings, it seems likely that the police would have used samples to clinch convictions, which would then have been that much harder to overturn. DNA evidence goes unchallenged in court and as the database expands clearly the opportunities to 'fit up' suspects will increase.

The vast majority of police officers are upstanding servants of the community, which is how I'd like them to remain. But too much power will change that.

As a nation, we need to have more confidence in people's ability to determine the course of society during difficult times. In an excellent article in the Daily Telegraph, Janet Daley commented on the ingenuity of and the sacrifice made by ordinary people during the floods. She ended with a suggested sentence for David Cameron's speech writers. 'It is because of that faith we have in ordinary people and their ability to do the right thing that we want to entrust them with more power over their lives and communities.'

We begin by resisting this demonic move to criminalise us with this database.