LAST time the Commons debated the 42 days detention proposal, Labour peer Helena Kennedy QC wrote to the Grauniad stating that government whips were using her alleged support for the measure to try to convince dissenters to get in line. In fact, the Baroness pointed out in her letter, she was against the measure (of course).

I don’t know if the whips had tried to use this particularly ill-judged incentive to win the vote; my view at the time was that telling back benchers that Helena Kennedy was against the measure would have been enough to swing more than a few votes the government’s way.

Today, inevitably, the Lords will vote down this measure. Such a move will be welcomed by the civil liberties groups (Shami Chakrabarti will have a very busy schedule flitting between studios), as well as by the legal fraternity (represented by) the Tories, the LibDems and some on Labour’s back benches (including some who, only a few short weeks ago were appearing on telly to lecture colleagues about loyalty to the prime minister: “Labour in chronic irony shortage shock!”).

It’s no secret that, along with the great, wise majority of our nation, I support a radical extension of the length of time the police can detain terrorist suspects without charge. I don’t see it as a civil liberties issue at all – more of a civil protection issue. I won’t rehearse all the issues now because, unfortunately, most people have made up their minds about where they stand, and aren’t going to change their minds now. Not yet, at least.

So the Lords will knock it back to us in the Commons, and we’ll have another vote on it, which I hope we will win. However, given the arithmetic in the Commons, that’s not guaranteed. If it falls in the Commons, then it’s game over. But only for now.

Because events, sometimes terrible events, happen. At some point in the future, the government will receive enough support to extend pre-charge detention to 42, or even 90, days. I hope it is done at a time where the arguments can be aired and analysed in a calm, rational atmosphere.

My greatest fear is that if the current proposal falls, the next time we debate extending pre-charge detention will be in the aftermath of another terrorist outrage. Undoubtedly, that will be called scare-mongering, as were all the warnings that were heard in the run-up to 7 July 2005.

UPDATE at 7.36 pm: As expected, their noble lords bottled it and defeated the government by a whopping majority of 191. I fear they won’t be the only people celebrating tonight. The government is to make a statement at 8.30 pm on its response.