What begins as an informal, well-intentioned conversation over soft drinks at a London hotel can end a few weeks later in a lonely act of suicide in an Oxfordshire field. That is a melodramatic but not inaccurate summary of the last days of David Kelly's life.

Dr Kelly, a UK government biological weapons expert, was certainly letting off steam when he spoke to the journalist Andrew Gilligan towards the end of May 2003. He was unhappy at the way in which unreliable information concerning Saddam Hussein's arsenal of weapons had been presented to the public.