But this New Labour policy should not be seen in isolation or as a necessary aberration in the face of a terrorist threat. It is part of a consistent theme revealed to me years ago by a former Government Chief Whip.

I had been invited to her room to discuss my my persistent failure to support the Government on legislation concerning human rights. It was not an unfriendly meeting. I expressed the view that the continued and continuous erosion of individual and political freedom would prove disastrous at the ballot box.

She smiled wearily with disbelief. "People in my constituency don't give a damn about civil liberties," she said. There were three depressing things about this statement. The first is the remote possibility that it may be true. The second is that she firmly believes it is true and the third is that she obviously approves of it. In her view the collective indifference of her constituents chimes precisely and accurately with Government policy.

Civil liberties, she might just as well have said, are just "so Old Labour". And there is no doubt that she speaks with the authentic voice of the New Labour Project.

The aversion to traditional freedoms reflects a more fundamental belief that modern politics are not about principle, but populism and prejudice.

At the heart of this psephology stands Mondeo Man, the famous, symbolic, unprincipled voter invented by Tony Blair. This car-polishing political animal is, according to the prophets of New Labour, motivated entirely by self-interest and individual advancement as opposed to the collective or communal good. To this individual, it is said, universal civil liberties, the ultimate collective values, are the subject of indifference, even contempt. He (or she) "doesn't give a damn".

The unprecedented and immense value of David Davis's by-election is that it will put this dismal and cynical assessment to the test as a single, stark issue.

It may well also bring to an end a depressing aspect of policy which has come to dominate politics for the past 30 years. Before the 1970s, remarkable to relate, no manifesto of any major Party mentioned crime and punishment as a part of policy.

This issue was widely perceived to be a matter of theology for churchmen, not politicians. In the 1970s, this altered dramatically as a result of a crude political masterstroke by the Tory party. Labour had traditionally been regarded as the political custodian of liberty, a reputation based upon the struggle for trade union rights and wider rights of protest.

The Tory strategists of the day perceived that it was but a short step to portray this reputation as sympathy for the criminal and the troublemaker and this they did to deadly effect. The reputation of being "soft on crime" was hung like an albatross around the withered neck of the Labour Party throughout the 1970s and '80s.

Then came New Labour. It became a central part of the Project to outflank and ambush the Tories on crime and punishment.

This was to be achieved by a total volte face on civil liberties. In order to extinguish its libertarian legacy, the New Labour Government has, since 1997, launched sustained legislative assaults on principles of justice and liberty regarded for 800 years as sacrosanct. The right to jury trial, the right to silence, habeas corpus and the presumption of innocence itself have all been the subject of sustained and systematic attack. Nor has this simply been an erosion of established rights.

The proposal for a vast secret government database worthy of the Stasi is the true centrepiece of identity card legislation.

This seismic political shift has totally changed the Parliamentary landscape and it is against this background that David Davis's unique, courageous and individual decision must be seen.

The attempt by Gordon Brown to dismiss it as a "stunt" is, of course, an alibi for failing to address the argument before a real electorate. The failure of the Government to carry the argument on 42 days was starkly illustrated by the lamentable means by which it achieved its majority on back of the Unionist vote. Claims by Irish MPs to have been motivated by pure principle, and not offered advantage, might have assumed minimal credence if a single one of them had attended the debate.

That fundamental British freedoms should be traded in such a fashion is a genuine political outrage on which David Davis has mounted this historic challenge. On this issue he deserves (and will, I suspect receive) overwhelming support and a clear message that his constituents do indeed give a damn.


Bob Marshall-Andrews QC is the Labour MP for Medway. He is backing David Davis's by-election campaign and is due to visit Haltemprice and Howden today.