Brown will cooperate. He saw what happened when the last regime played silly buggers with the Met. The all important question is how far the police will investigate. Will they just nick Peter Watt, or ask who else used such circuitous donation routes. And does Watt look like the sort of chap who would allow himself to be demonised as the only villain?
The biggest problem for Brown is that not just that he may be the second prime minister in British history to be questioned in a criminal inquiry. As Lady Luck dumps on him, he is being tried in the court of public opinion. And as tomorrow's Telegraph/YouGov poll will show, they are fast making up their mind.