Yet the standards of proof in Australia, for shoplifting as much as murder, is "beyond reasonable doubt". Unless that standard is reached, our law regards a person as not guilty.

Most of the men and women who have been acquitted of murder in Australia in recent years were "probably guilty", in the sense that there was cogent evidence pointing to their guilt. The police and prosecution system may have shortcomings, but it is rare for a complete patsy to appear before a judge.

The murder of Colin Winchester was a terrible and sensational crime. No Australian policeman so senior had ever been assassinated. There was never a limit to the resources available to the investigation, and those who ordered the investigation, from the prime minister down, were conscious from the start that the investigation would come under great scrutiny. The relatively newly formed Australian Federal Police were swamped with offers of assistance from other, in many cases, more experienced forces.

At the start, the working assumption was that the murder was the work of Italian organised crime, and, last week, Acting Justice Brian Martin said that there was a hypothesis about this which was consistent with Eastman's innocence, though, at this stage, it was hard to say how strong this case was.

But the AFP decided to treat the investigation as a local matter, to be investigated by its local cops, not even the most experienced investigators in the AFP. Almost all involved had been close friends of Winchester and had worked under him. Not a few had worked on some spectacularly botched earlier ACT murder investigations, which, in a more critical system would have seen them moved on.

No one has suggested that there was corruption or bad faith in the way that the inquiry came to concentrate on Eastman, but there was a good deal of corner-cutting and disingenuous dealing with the public, the Coroner, the prosecution system and the Ombudsman about the manner of the inquiry. The police belief, fueled by commissioned psychiatric reports on Eastman's mental condition, that Eastman might "crack up" and confess, or do something such as lead them to the murder weapon, led to considerable police impropriety.

The investigation seems also to have become infected by tunnel vision, by which any evidence which pointed to Eastman's guilt was seized upon, while evidence which did not tended to be ignored or cast aside. Police had ample warning - indeed they gathered but did not use some evidence themselves - that their main forensic witness, Robert Barnes from Victoria - was not reliable. But they did not want to know, and did nothing about it, perhaps for fear that what they discovered might weaken the case.

Prosecutors themselves were accused of withholding information from the defence. Martin says that they did not mean to - indeed that they took their disclosure obligations seriously. Nonetheless, he says that it became clear that a good deal of material, including material disclosing considerable weaknesses in the forensic case was never disclosed to the Eastman lawyers, whether by oversight, because it had been regarded as legally privileged, or because it had not been explicitly asked for. This was on top of the fact that the prosecution was unaware of some material not passed on by police. The consequence was that Eastman was denied a fair chance of acquittal. Had the Court of Appeal known of what happened, it would have quashed the verdict 18 years ago.

The Eastman case was in the relatively early days of modern forensic science. But it was after two sensational cases where justice had miscarried because forensic scientists had misinterpreted evidence, and got things badly wrong. One was the Azaria Chamberlain case. Another was the Edward Splatt case in South Australia, in which a completely innocent man was convicted of murder on scientific evidence. Both cases had involved confident scientific witnesses who had lost detachment and become advocates, and major scientific failures of documentation, reproducability of results, the maintenance of continuity of evidence, prevention of contamination, peer review and close records of processes of deduction. All were to become features of the Eastman case.

Each case had led judges to write guidelines about improving and developing "expert'' evidence. Had police, or prosecutors, followed the rules then laid down (as well as more modern ones developed later) the deficiencies in Barnes's conclusions would have been obvious. But Barnes was "difficult" and resistant to external review, and, at times threatened to walk away unless he got his way. More effort went into placating him than in verifying results.

The weakness of Barnes as a witness, and reasons for doubting him, were obvious from at least 1996, but should have been by 1993. But there was never a post-trial review, and efforts to re-open the matter in the numerous appeals seemed to founder on the confident assumption by judges that even if Barnes had got it wrong, police and prosecutors would have discovered it. Ergo, no great reason for concern. One judge who conducted a review used just these results to declare that he was completely convinced of the man's guilt.

The inquiry had minimal help from police or the prosecution system, which spent millions attempting to prevent it happening or to rein it in. Their lawyers at the inquiry were not seeking to have the truth established, but trying doggedly to prevent any criticism of their clients over events 25 years ago. No new material about the case was provided. The production of records, generally under subpoena, was slow and grudging. Neither the AFP nor the DPP have ever conducted a review of what they did in the case; a reason why the failures and the ineptness must be regarded as systemic ones extending to the present day. Likewise, there has yet to be any sort of examination of conscience by ACT Crown law authorities over their role and advice in the matter.

Defenders of what occurred will point to the judge's hint that Eastman is probably guilty anyway, and to what the judge said was the strength of the overall cases against Eastman. But it is worth remembering that the terms of reference of the inquiry were tightly confined, and even then argued by the DPP and AFP to be too wide. The inquiry had no remit to examine the general case against Eastman. There could be such an inquiry, if Simon Corbell had the guts to have it, and some of Eastman's defenders would relish the opportunity to demonstrate further weaknesses and miscarriages of justice.

Willy nilly, I have been involved in the case from the beginning. I knew Eastman and the victim beforehand, and I even knew something of the circumstances of the supposed motive. I was alerted early about the incident, and, driving from home into work, drove near the murder scene even as police were setting up barricades. A good many senior AFP officers heard of the murder from me, and that night, I wrote an obituary of Colin Winchester.

The trial seemed to me to be a travesty, even if it were true that Eastman's antics were the primary cause. Yet much of Eastman's behaviour or misbehaviour arose because Eastman believed the judge and prosecution were indifferent to a campaign of police harassment - of "in-your-face'' open surveillance - that had manifestly been occurring, despite bland police denials. Eastman may have been unduly paranoid - even Acting Justice Martin, who does not accept that he was mentally unfit to be tried, says that. But that did not mean that people were not trying to "press his buttons".

I did not report the investigation, inquest, trial or innumerable appeals and collateral actions from day to day. That was done by the incomparable Roderick Campbell, a great legal reporter who may well have written two million words on the case before he died. Campbell had no affection for Eastman but was very fair-minded, and entertained a lot of doubts. So did I, and many others over the years, even if Eastman was never able to attract a fan club in the manner of Lindy Chamberlain. To this day, the shadow of the case hangs over the reputation for capacity and competence of the AFP and the ACT justice system.

A former ACT Attorney General, Gary Humphries has pointed to the millions of dollars this case has consumed, including in legal aid, in some sort of defence against any suggestion that Eastman was left to rot for 20 years. Yet it reflects badly on the system that until recently all that expenditure did nothing to advance Eastman's interests, or the cause of justice. Almost all of the problems identified by Martin were obvious in the 1990s. I think they would be repeated today by the fresh generations of people who will not listen and will not learn.