Leading article: A consensus that needs to be challenged

Now they have reopened with the declaration by Mark Oaten at the Liberal Democrat conference yesterday that his party would not give the Government a "blank cheque" for its anti-terrorist legislation. The cross-party consensus on security is on the verge of being broken - and this is all to the good.

Immediately after the 7 July attacks, the Prime Minister said that no action would be taken in haste. Within days of the second - failed - attacks two weeks later, however, there was talk of reconvening Parliament to consider new legislation. And while Parliament has not been recalled, some of the new anti-terrorist measures have seen the light of day, presented first by the Prime Minister, and this week in more detail by the Home Secretary.

Mr Oaten, the Liberal Democrat spokesman on home affairs, said his party would vote against two particular sections of the Bill. The first is the planned extension of custody without charge to a maximum of 90 days. The other is the proposal to make "glorifying" terror a criminal offence. Mr Oaten was devastating in his criticism of both, and he was right.

An extension of the maximum period of detention without charge from 14 to 90 days is a vast increase, wholly unjustified by the circumstances. It comes close to internment. This is a policy that failed in Northern Ireland, and there is no reason at all to suppose it would work across the whole country today.

As for the proposed offence of "glorifying" terror, it is hard to improve on Mr Oaten's description of it as "a dangerous proposal, hard to define in theory, unworkable in practice and putting freedom of speech at risk". Indeed.

Were this anti-terrorism Bill to pass through the Commons in anything like its current form, it is to be hoped that it would face the same fierce opposition in the Lords as has repressive legislation proposed by this Government in the past. For it to get to the Lords without challenge, however, would be a sad reflection on the quality of our democracy.

Security, in the wake of the London bombings, is inevitably a popular cause. And it is to the Liberal Democrats' credit that they are prepared to break the political consensus in the name of defending our civil liberties. The Home Secretary should listen attentively to the objections before his Bill goes before the Commons.