By Jon Silverman Legal affairs analyst

But beyond confirming that the prime minister, defence secretary, Geoff Hoon, Alastair Campbell and other key players will be called to give evidence, what else did we learn? A surprising amount given the opening lasted only 30 minutes.

First, although Lord Hutton has mapped out the pathway to discovering the truth behind the death of Dr David Kelly, he is not being rigidly prescriptive about the best way to get there.

Lord Hutton is not ruling any issue out-of-bounds

This is why he is dividing the inquiry into two phases, with the second one intended to home in on those areas which he considers most germane to his remit.

This will involve recalling some witnesses who have the most questions to answer and probing them in greater detail.

They will be informed in advance if they are subject to attack or criticism - something which the Scott Inquiry into the arms-for-Iraq affair failed to do - and allowed to appoint counsel to cross examine on their behalf.

Additional witnesses may also be called. There could be some fireworks during this second stage of the inquiry.

Second, Lord Hutton is not ruling any issue out-of-bounds.

If, for example, he considers it relevant to ask about the way in which intelligence for the now notorious September dossier was gathered, he will allow such questions to be asked.

We may get an early indication of the scope of questioning since the first witness will be from the Ministry of Defence to talk about Dr Kelly's expertise in weapons of mass destruction and his involvement in the drawing up of the dossier.

Confidential letters

Third, it is clear that no one will be spared any embarrassment considered necessary to get at the reasons for Dr Kelly's death.

By peppering his opening chronology of events with details of confidential letters - from the defence secretary and the BBC chairman, amongst others - which are amongst the mass of documents he has already received, Lord Hutton was setting down a marker.

It is his intention that nobody should be allowed to hide behind any obfuscation, whether they are ministers, civil servants or journalists.