I name the guilty ones. ... In an age when journalists are turning into quasi-politicians, appearing as co-equals on programmes such as Question Time, it is right that they should be ruthlessly monitored by each other. That is the function of a media column, a genre that did not exist 20 years ago, and which has grown along with the egos, picture bylines and general importance and self-importance of journos. [via Boris Johnson MP]
Boris allows himself to be portrayed as a twit, whether you agree with him or not his writing is interesting and thought provoking.
On this particular issue, Tom Baldwin should answer the question he refused to answer at the Hutton Inquiry - who briefed him. Without an answer it seems reasonable to me to assume it was Mr Campbell.