In Orwell’s 1984, “doublethink” meant “the power of holding two contradictory beliefs in one’s mind simultaneously, and accepting both of them”. The work of places such as the Ministry of Truth, enabled people “to tell deliberate lies while genuinely believing in them”.

You cannot help thinking of that when listening to politicians chillingly defending the proposal that British freedoms would be protected by a law under which someone can be locked up in a cell for six weeks without even being charged.

The Prime Minister has said that safeguarding the British people under threat of terrorism will be achieved by “a careful and proportionate strengthening of powers”. Plainly, the six-weeks-in-a-cell option is an alarmingly disproportionate state power. And it is utterly useless to tell people not to worry because this draconian power will be used sensibly. You maintain a civilisation by preventing the existence of draconian detention powers not by giving the State such powers in the hope they’ll be used safely.

The safeguards offered by the Prime Minister are wholly unconvincing. He says, for example, that a lot of time is now needed to investigate cases and in the 2006 alleged airline bomb plot there were under scrutiny 400 computers, 8,000 disks and more than 25,000 exhibits. First, as six weeks were not needed in that case, it is an odd choice of example from which to seek support. Secondly, if there is a need for more “investigating officer time”, that is a resource question, not a reason to erode historical British liberties as a cheaper option than paying for more police officers.

There have appeared in this debate some very disturbing ideas. One is that a vote against the 42-day detention proposal is a vote for al-Qaeda. The opposite is true. If we cravenly bow to terrorism by changing our laws so the State has severe powers and the citizen’s rights are weakened, the terrorists have had a triumph. After 9/11, the Government said it would not be terrorised into changing Britain — just what it’s now set to do.

Gordon Brown asserts that he is “upholding something that is at the heart of the British constitutional settlement: the preservation of civil liberties”. How could anyone, outside the Ministry of Truth, speak about preserving civil liberties while zealously cutting them away?

The author is the Professor of Law at the Open University

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