Lord Hutton presiding over the inquiry
An at-a-glance guide to Lord Hutton's report into the death of government weapons adviser David Kelly.
What did the report say?
Lord Hutton's report, 328 pages in all, criticised the reporting of BBC journalist Andrew Gilligan, saying that allegations he made against the government were "unfounded".
In his report on the Today programme on 29 May 2003 Mr Gilligan said that claims made in Tony Blair's intelligence dossier on Iraq - that Saddam Hussein could launch attacks with weapons of mass destruction within 45 minutes - were probably known to be wrong by the government before they were placed in the dossier.
Lord Hutton also criticised the management of the BBC saying it failed to check the details of Mr Gilligan's story as soon as the government complained that it had raised grave charges against them.
Why did Gavyn Davies and Greg Dyke resign?
Gavyn Davies was the chairman of the BBC's board of governors. The body has 12 members who oversee the BBC and appoint the director general.
Mr Davies was the first member of the corporation to resign after Lord Hutton's report criticised the governors for not investigating the government's complaints about Andrew Gilligan's story themselves, relying instead on the word of the BBC's management.
Mr Davies' resignation was followed the next day by that of the director general, Greg Dyke.
As director general Mr Dyke was ultimately responsible for all the BBC's output.
He stepped down saying: "If in the end you screw up, you have to go." He also spoke of his hope that his resignation would draw a line under whole affair.
Why was the Hutton Inquiry called?
Tony Blair announced the inquiry following the apparent suicide of scientist David Kelly. Dr Kelly was the source for Andrew Gilligan's story.
During the summer of 2003 Dr Kelly was at the centre of speculation over who was the source behind BBC reports which looked at the government's reasons for going to war.
What events led to the inquiry?
Reporter Andrew Gilligan also said on the Today programme that a source had told him Downing Street asked for certain intelligence to be given undue prominence in the dossier.
The government denied the claim and called for an apology from the BBC, but this demand was rejected. Tony Blair said the claims undermined his integrity.
Three days after Dr Kelly was quizzed by MPs about whether he had been the source of Gilligan's report, his body was found near his Oxfordshire home.
Who is Lord Hutton?
Baron Hutton of Bresagh, who wrote the report was one of the UK's most senior judges.
He spent much of his early career in Northern Ireland, where he was junior counsel to the attorney-general.
He became a Law Lord in 1997 after nine years as Lord Chief Justice of Northern Ireland.
Who was Dr Kelly?
David Kelly was an Oxford-educated microbiologist who joined the Ministry of Defence in 1984, working for much of that time as a scientific adviser to the ministry or its agencies.
The 59-year-old was an expert in arms control having worked as a weapons inspector in Iraq between 1991 and 1998, following the first Gulf War.
Former colleagues described Dr Kelly as highly professional and well respected. He was once nominated for a Nobel peace prize.
He was married with three daughters and lived in Oxfordshire.
How did the inquiry work?
Inquiry hearings were held at the Royal Courts of Justice in London. All were in public, although members of the Kelly family, MI6 chief Sir Richard Dearlove and an intelligence official involved in sensitive work all gave evidence via an audiolink.
Lord Hutton spent the first part of the inquiry establishing a chronological record of what happened, with relevant parties questioned by the inquiry's legal representative.
A number of witnesses were then recalled and others summoned for the first time to face cross-examination during the second phase of the investigation.
He then wrote his report which was published on 28 January 2004.