The Met appears to be in headlong retreat this morning. The acting commissioner has just appointed a chief constable to carry out an urgent review of the handling of the arrest of Damian Green and the Home Office mole. The question it needs to answer is how an everyday Whitehall drama has been turned into a major constitutional crisis.
As I reported the other day, the police took the view that they had to arrest the Tory frontbencher for the same reasons that they had arrested Ruth Turner in the cash for honours investigation.
In other words, in order to gain access to computer hardware, mobile phones and documents an arrest was necessary because the individual was unlikely to volunteer the material. Not so, say some police insiders. The production of a warrant would have done the trick, or better still, an invitation to the individual to cooperate or face the embarrassment of a warrant or an arrest. The Met have made the first move. We now wait to see how the Speaker will react.