Supporting Britain's top cop?

Len Duvall chairs the Metropolitan Police Authority

Not so long ago, if there was a problem at Scotland Yard, the only person the Metropolitan Police Commissioner needed to satisfy was the Home Secretary.

The two men - and it has always been men - would often meet over a glass of whisky to agree how London should be policed.

Labour thought that was an anachronism and five years ago, it created the Metropolitan Police Authority, the MPA. It's job is to make the force democratically accountable in order to bolster public trust in the Met.

That trust has taken something of a knock with the killing of Jean Charles de Menezes. Some politicians have questioned whether the policy which allows police to shoot a suspected suicide bomber without warning - Operation Kratos - has been properly debated.

Although an investigation by the Independent Police Complaints Commission is underway, the Commissioner Sir Iain Blair today used a newspaper interview to defend his force.

After the investigation is over, it's the MPA which will decide Sir Ian's future. Len Duvall, a Labour member of the London Assembly, is the Chairman. As well as asking him about the Commissioner, Shaun Ley talked to him first, about Operation Kratos. When did he learn of its existence?