Police tactics may be heavyhanded, but no Home Secretary can start issuing apologies until the case is over

Imagine for a second that John Reid, Home Secretary at the time, had hit the airwaves to attack the heavyhanded actions of the police after they launched their dawn raid on a senior female Downing Street adviser, before arresting her in the cash for honours affair. That he might have been justified in thinking the actions wholly disproportionate - as her subsequent exoneration proved and those who knew her believed at the time - is beside the point. He would have been wrong actively to intervene during an active investigation. And I'm pretty sure the Tories would have been the first to say so.

The same is true of Jacqui Smith today with respect to the arrest of Damian Green. She should not and cannot take the course of action being advised by David Cameron and 'condemn' the police, nor indeed can Gordon Brown, though he could do more publicly to uphold the rights of MPs. And Smith certainly cannot start issuing apologies until the matter is closed. Whatever we may think about the police actions in this case - and I share the views of my former boss on these matters - no Home Secretary can get in the business of trying to take operational control of the police. Were they to do so, we would then be living in an authoritarian state. And I seriously doubt that any of those claiming that we are now living in a police state realise what that really means: for a start, we certainly wouldn't be hearing their claims on the airwaves.

Harriet Harman is right to say that there should be a review of procedures to develop much clearer protocol for police seizing MPs' files and computers, especially in the Houses of Parliament. But David Cameron and would-be Home Secretary Dominic Grieve are utterly wrong to suggest that either Jacqui Smith or Gordon Brown should intervene to overrule or rebuke the police in this case, just as they would have been wrong to do so - however unjustified the action seemed to many of us - when the police took similar action before. When this case is over - or if it is decided not to press charges against Green - there should certainly be a proper review of police tactics in this and similar cases. But not before.