I regard democracy as the most radical and revolutionary idea of our time. The powers that rule us talk about it. But they resist it with all the wiles and techniques at their command.

It used to be clear that the ruling classes had the wealth, authority and power while those underneath did not. This started to change when the right to appoint our rulers moved from the wallet to the ballot. Now they are doing everything they can to preserve their power. This is why democratic rights and civil liberties are so important and essential. We must now preserve our right to speak, to assemble, to organise, to move around freely and protect our identity, and not become crushed by the state.

Only last week I was on my way to the House of Commons when I was pulled over by the police. They said that because I was close to a "government establishment" they were stopping and searching me and my car under anti-terrorism powers.

Being questioned by the police under suspicion of being a terrorist is not a pleasant experience. I would not wish it on anyone. More important, will all the details they took now be registered on their database? Will I become a terrorist suspect on the grounds of their random stop and search? Can I be informed of this? I have written to the home secretary to ask.

In my case I know how to do this. The experience may be much more intimidating for other members of the public. It may prevent them from demonstrating or speaking up when they wish to. This is a small example of why the attempt to impose ID cards, which will become a generalised permission to control us, is entirely wrong.

This is why I went to support David Davis when he took the issue to his constituents in Haltemprice and Howden last summer. He was quite right to protest that the House of Commons was not doing its job, and to take the issue to the voters the best way he could. Support for imprisoning people without charge dropped considerably thanks to his campaign alerting the public that it would give permission to the police to hold the innocent at will. Opposing this is not a left or right issue, it is a fundamental and deeply radical principle.

With its new website liberty central and its support for the Convention on Modern Liberty on 28 February, the Guardian has now taken up this issue. I don't always agree with the Guardian. But with all respect nor do I agree with one comment that has been forwarded to me which says, "The Guardian promotes a site based on Tory principles of liberty and small government? Hooray!" Or another that says, "I am suspicious of this liberty push, because most of those involved seem to sidestep the issue of social justice and equality."

Of course we need good government. Of course we need it to have policies that deliver greater social justice and equality. But the more influential government becomes the more it is essential that it respects our liberties. Its obligation must be to serve the people, not rule over them. We have to insist on this principle. It is not a matter of left or right, Tory or Labour.

In fact it is essential to defend liberty to the hilt especially if, like me, you want a government that can protect the weak and vulnerable. The more government has influence over economic and social policy, the more democratic, open, accountable and respectful of our liberties it needs to be. Otherwise, if it is not based on the wishes of a free people, the rich and powerful corporations will take advantage of any lack of democracy.

We all know there are rightwing libertarians who want liberty and have a different approach to economic and social policy. All the more reason not to allow them to walk off with our fundamental principles. Long live liberty!