Along with Tony Cragg, his former deputy, Sir Joe's evidence could create further problems for the Government when the circumstances surrounding letters expressing concerns about intelligence material in the dossier - notably one from Brian Jones, head of the scientific wing of the Defence Intelligence Analysis Staff - are revealed.
They will be asked to explain why Dr Jones and his colleagues received no response to their complaints, and why their concerns were not reflected in the final dossier published in September 2002.
Other witnesses include Sir Richard Scott, who worked with Dr Kelly at Porton Down, and two unnamed witnesses described as "security staff". The BBC director general, Greg Dyke, will also appear.
On Tuesday, however, the inquiry will return to original witnesses whose testimony threw up questions or discrepancies that either Lord Hutton or counsel for the various parties - the Government, the BBC and Dr Kelly's family - want answers to. Mr Hoon's recall is widely viewed as a certainty.
Questions arose about the Defence Secretary's role in the strategy to name Dr Kelly. Though he insisted he had played only a limited role, evidence from his special adviser, Richard Taylor, later put the Defence Secretary centre stage. And new evidence from the report of the Commons Intelligence and Security Committee - which complained that he had not been immediately forthcoming in providing letters proving concern in the intelligence community over the dossier, behaviour that was "potentially misleading" - could raise further questions.
It is understood that the Kelly family also want to hear again from Tony Blair, after he claimed the scientist knew his identity would become public. Alastair Campbell, Mr Blair's outgoing director of communications and strategy, is also tipped for a recall to explain the 15 changes he proposed to the draft dossier, including beefing up the "45 minute" claim.
John Scarlett, chairman of the Joint Intelligence Committee, could be asked back to explain why material in the dossier was "hardened" after Mr Campbell's request. The BBC reporter Andrew Gilligan, whose Today programme report that No 10 had "sexed up" the September dossier, is also highly likely to return to the witness stand.
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INDEPENDENT
Hutton inquiry website
British Parliament Foreign Affairs Committee transcript:
Evidence of Dr David Kelly
Key players in the 'sexed-up dossier' affair
Herald Feature: Iraq
Iraq links and resources