Crucial questions that the BBC and the Government must now answer

Lord Hutton's investigations will shine a rare light on decision-making processes both at the upper echelons of the corporation and in Whitehall. By Andrew Johnson

Lord Hutton said his inquiry into the death of Dr David Kelly, which began on Friday and will resume on 11 August, was solely to "investigate the circumstances surrounding" the weapon inspector's death.

He did not, he said, sit to decide between the "conflicting cases" of the BBC and the Government.

But Dr Kelly found himself at the centre of the furious row between the two institutions over whether or not the Iraq dossier had been "sexed up" by No 10. And untangling their arguments, claims and counterclaims is the only way to shed light on the circumstances surrounding his apparent suicide.

The results, therefore, could seriously undermine public confidence in the Government, the BBC or both. Lord Hutton's questioning will go to the heart of the decision-making processes of both organisations, and for the first time the public will discover what goes on between ministers and their officials behind closed doors, the nature of their relationship with the media and how the BBC works.

It will not look at the wider issue of why we went to war with Iraq. These are just some of the questions Lord Hutton needs to find answers to:

What was the degree of Dr Kelly's involvement in the Iraq dossier, which claimed Saddam Hussein had weapons of mass destruction?

In his report the BBC journalist Andrew Gilligan described Dr Kelly as "one of the senior officials in charge of drawing up the dossier".

But Dr Kelly is said to have only written one chapter of the dossier and contributed some analysis.

What did Dr Kelly tell Andrew Gilligan, Gavin Hewitt and Susan Watts in his discussions with them?

The BBC reported that the dossier had been "sexed up" by Downing Street. Mr Gilligan went further in an article in the Mail on Sunday, naming Alastair Campbell as responsible for exaggerating the claims.

But in a letter to his superiors Dr Kelly said: "I did not recognise myself as the source."

Did Dr Kelly lie to his superiors and the parliamentary committee?

In evidence to the Foreign Affairs Select Committee, he said he could not remember speaking to BBC reporter Gavin Hewitt, whom he talked to on the telephone on 29 May. He appeared uneasy and evasive before the committee.

Was Mr Gilligan justified in implying that Alastair Campbell had ordered the 45-minute claim to be inserted into the dossier? Was Dr Kelly misrepresented by Mr Gilligan?

Mr Gilligan told the committee that the "source did not say either that Mr Campbell did not insert it or that he did insert it". He added: "The claim was that the dossier had been transformed, and I asked 'How did this transformation happen?' and the answer was a single word 'Campbell'."

Why did Mr Gilligan go further in an article he wrote for the Mail on Sunday than he was prepared to go in his BBC broadcasts?

The Mail on Sunday article accused Mr Campbell of sexing-up the dossier. Mr Campbell was never named in the original BBC report.

Who was responsible for allowing Dr Kelly's name to be leaked to the press? How much did Tony Blair know of these decisions?

Dr Kelly had spoken of being upset when his name was publicly revealed. He had been promised confidentiality by his employers. Yet, in a highly unusual move, the MoD press office agreed to confirm the name if journalists managed to guess it.

Did the Secretary of State for Defence, Geoff Hoon, know of, or make the decision to confirm, Dr Kelly's identity as Mr Gilligan's source?

On the day the name was leaked he met the MoD's permanent secretary, Sir Kevin Tebbit. Mr Hoon denies any impropriety.

Why did the BBC not name Dr Kelly as the source of their stories, or confirm his name privately to the MoD after he came forward?

On 8 July, Mr Hoon wrote to Gavyn Davies, chairman of the BBC board of governors, stating that an individual in the MoD had come forward to say that he had met Mr Gilligan. The BBC, in protecting its sources, refused to confirm or deny who its sources were.

Was pressure placed on Dr Kelly between his coming forward to his MoD bosses and his appearance before the parliamentary inquiry?

Reports have claimed that Dr Kelly was threatened under the Official Secrets Act and with the loss of his pension. The MoD has explicitly denied this.

What help was Dr Kelly given to deal with the intense pressure, considering his state of health?

Lord Hutton revealed on Friday that Dr Kelly suffered from coronary artery disease, a condition that would not have been helped by the intense media spotlight he was subsequently put under.

Was Dr Kelly treated too harshly by the parliamentary committee?

Unlike most experienced politicians who go before select committees, Dr Kelly appeared shy and inexperienced.

What is the significance of the four electrocardiogram pads found on Dr Kelly's chest after his death?

The existence of the electropads is something of a mystery, revealed in the inquiry's opening session on Friday.