Why is Gordon Brown still pushing ahead with this after all his past difficulties?

This is, without doubt, an issue over which Gordon Brown is seeking to redefine himself after the disasters of the last few weeks. Labour advisers are saying that talking policy - and getting away from a succession of events that are out of his control - is a key way for the Prime Minister to put these troubles behind him. Picking a fight like this suits Brown, and he's probably glad that the Conservatives have opposed him. By signifying his willingness to sacrifice some civil liberties in exchange for security, he aims to come through as a strong leader taking a principled stand in the face of opposition.

But haven't police specifically requested this measure?

Yes. Sir Ian Blair, the Metropolitan Police Commissioner, has called for an increase in the minimum period of pre-charge detention as has Sir Ken Jones, the President of the Association of Chief Police Officers. Ministers say they have been presented with professional judgments from both men that recent cases suggest a trend of greater complexity, with more international links and more material to be examined particularly from computer discs. They argue that it is only a matter of time until police will require longer than 28 days, and that it would be preferable for the law to be in place rather than emergency legislation introduced in the aftermath of a serious terrorist incident.

Is there any evidence that police have needed longer than 28 days until now?

No, there have so far not been any cases where police have had a suspect for 28 days and had to release him because of the limits in the current law.

The Conservatives claim that the Government already has emergency powers to increase detention. Is this true?

The Government argues that extending pre-charge detention for terrorist suspects should be done specifically in counter-terror legislation rather than laws dealing with emergencies. Ministers also claim that it is not certain the the Civil Contingencies Act could be used to detain individuals rather than simply restricting their movements. In addition, the Civil Contingencies Act could not be used in all circumstances where police might need to detain a suspect longer than 28 days. The Home Office says that it might be possible to use the Act in a 9/11 type attack where there is a significant disruption to the life of the nation, but it might not be possible to use the Act where police have disrupted or foiled a complex plot and suspects have been arrested. This is because there is some doubt as to where such a case would meet the test of being an emergency which threatened serious damage to the security of the UK - opening up a huge legal argument.

Are Opposition parties, or backbenchers, more likely to support these proposals than previous ones?

The Conservative and Liberal Democrats appear to remain opposed to the plans but it is unclear how the Labour backbenchers will react. By coming up with a compromise limit of 42 days, instead of 56, Jacqui Smith and Gordon Brown have clearly taken a judgement that they can win the argument with their backbenchers, and squeeze this measure through. Clearly, they believe they have done enough to meet the concerns of all but the most die-hard opponents of extension within their own ranks.

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