This is a measure that will allow the Home Secretary to impose on an individual six weeks' detention without charge, on the basis of police suspicion rather than hard evidence, and without formally accusing them of any criminal offence. Contrary to Tom Levitt's bland assertion of confidence, it is obvious that this changes quite a lot both in principle and practice.

This measure directly attacks our fundamental democratic principles of justice, fairness and liberty. It removes an individual so held from the fundamental protection of the law of habeas corpus. Innocent people will almost certainly be detained under this measure and then released without charge. Just think if it was you. Released after six weeks in police custody, how likely is it that you would still have your job and the trust of your community? What of the effects on your home, your family and your friends? The proposed weak oversight by Parliament and judiciary will be inadequate to prevent this and such compensation as they may offer will be too late and inadequate to redress the harm done.

This measure is unnecessary. There has been no case to date where longer than 28 days' detention has been needed. The Government's only argument, echoed by Tom Levitt, is that these powers might be needed in the future. What support there is from amongst the police is, at its strongest, equivocal. The Director of Public Prosecutions (responsible for charging decisions) has said longer pre-charge detention is unnecessary because charging practice has recently changed to help the prosecution charge terror suspects earlier.

Neither the growing complexity of terrorist cases nor the challenges posed by computers and geography have made it necessary for comparable democracies to even approach our current 28 day limit for pre-charge detention. The United States limit is two days (and I don't think anyone now is holding up Guantanamo as an example to follow), Spain is five days, Russia is five days, France is six days and Turkey is 7.5 days. Even if we were to accept Tom Levitt's argument on the '29th day atrocity' as a justification for extending the limit to 42 days, where do you stop with that? Do we then need to extend the limit to prevent an atrocity on day 43? And so on?

The measure being unjust will be counterproductive and will not make us safer. The Home Office's own Equality Impact Assessment states, 'Muslim groups said that pre-charge detention may risk information being forthcoming from members of the community in the future.'

There are better alternatives, such as those suggested by Liberty, that include: (A) allowing intercept evidence to be used in criminal trials so that the police can use existing surveillance material to support a charge; and (B) with judicial oversight, allowing the police to re-question suspects that have already been charged with an offence if new evidence comes to light suggesting that a more serious charge may be appropriate.