"And yet I don't see anyone from the House of Lords standing in a broom closet asking for Mr. Blair's resignation."
I've no idea what a broom closet has to do with anything. Lots of people have demanded Tony Blair's resignation over this issue, mostly on the anti-war side of his own party. These new allegations, while they may add to the depth of knowledge of the decision-making processes of the Blair Government, don't really contain anything substantially new and it doesn't seem to be generating much in the way of new outrage at the moment over here.
It is in reference to the fact that the demonRATS held their "hearings" to impeach President Bush, in a room in the basement of the Capitol building.