Leading article: Questions that will not go away

The families of four British soldiers killed in Iraq who are pushing for a public inquiry into why Britain joined in the US-led invasion are performing a valuable public service. By keeping the pressure on the Government on this subject they are ensuring that the highly dubious manner in which we were dragged into an unjustified conflict does not slip from the public consciousness.

The Court of Appeal, in ruling yesterday that the families are entitled to apply for a judicial review of the Government's refusal to hold such an inquiry, attempted to play down their expectations of victory, describing decisions on war an peace as "essentially matters for the executive and Parliament" rather than the courts.

But this did not stop the families' solicitor describing the verdict as a "stunning victory". We shall have to see what happens when the full hearing takes place in November. One cannot entirely write off the families' chances, given that the judges argued yesterday: "It is at least arguable that the question of whether the invasion was lawful - or reasonably thought to have been lawful - as a matter of international law is worthy of investigation."

Indeed it is. Furthermore, no matter which arm of our constitution prompts it - whether the judiciary, the legislature or the executive - such an investigation into how we were led into this conflict is necessary for the health of our democracy.

Whenever this matter is raised, Downing Street argues we should "move on" because all the facts have been gone over enough times. Not so. Much of interest about the run-up to the war did indeed come out of the Hutton Inquiry. But this addressed the death of the civil servant David Kelly, not the decision to go to war itself. The subsequent Butler Inquiry was enlightening too in some respects, not least in revealing how Tony Blair comes to decisions. But it did not address the central question of why we were taken to war either, instead focusing on flaws in the pre-invasion intelligence on Saddam Hussein's military capability.

Key questions remained unanswered. For instance: how did the deeply equivocal Government advice from the Attorney General of 7 March 2003 get changed within 10 days to the unequivocal assertion that the invasion would be legal? What commitments were made by the Prime Minister to the US President over Iraq, and when? And why did the public justification for the invasion keep changing?

Until we learn the full facts behind the calamitous decision to invade Iraq, public trust both in this Government - and the political system as a whole - will continue to decline.