One of the weaknesses of the Australian criminal justice system is that with many of the most significant miscarriages of justice in Australia the judicial system did not – seemed that it could not – recognise a fundamental mistake and a serious injustice. It was too used to mild correctives, and minor criticisms, but not to declarations that the system had failed. That even the courts had failed.

We cannot thank the courts for the fact that a grave injustice to Lindy Chamberlain and her husband was uncovered. They lost all of their appeals until the chance discovery of some fresh evidence led to an external review and exposure of just how flawed the case had been. Even then, a player in this week’s Eastman case was on his feet arguing to the last that the conviction should not be disturbed.

In Western Australia, a sequence of inquiries have seemed to suggest that its judges vie with the cops for being unable to get murder matters right, at great expense to innocent people. Courts and courts of appeal repeatedly failed to find any error or problem with the convictions of men whom we now know positively to have been innocent. These were men such as Darryl Beamish, a deaf-mute from whom police claimed to have extracted a voluntary signed confession. John Button - a man with a bad stutter which was interpreted by police as nervousness about his guilt - was assaulted by police during a 22-hour interrogation after which he also 'confessed'. Scientific evidence against him was also misrepresented. Andrew Mallard was convicted of murder after a long unrecorded police interrogation and a brief recorded confession. This was a case in which police were shown to have withheld evidence that demonstrated Mallard’s innocence.

In Queensland, Kevin Condren’s conviction for murder, based on police coercion and fabrication, was upheld on appeal and he served six years before his conviction was quashed after an external inquiry. Graham Stafford, also from Queensland, served 14 years, after a conviction for murder based on flawed scientific evidence. In South Australia, Henry Keogh served 21 years for murder before it was shown that police had withheld exculpatory evidence (and later, evidence pointing to the real murderer was discovered). Edward Splatt served seven years for murder and sexual assault in the same state before a royal commission showed that the conviction was untenable, scientific evidence was unreliable, and that there had been contamination of the crime scene.

Across the ACT border in Queanbeyan, Ziggy Pohl served 10 years for the murder of his wife, despite a lack of motive and steadfast details, and was then released on licence. Seven years later, another man walked into the Queanbeyan police station and confessed to having murdered Mrs Pohl during a botched burglary.

Despite such instances of wrongful conviction, moves by politicians to enable external reviews of contested convictions, whether along a model now working successfully in Britain or otherwise, have not got far. Police have zero enthusiasm, judges not much more. Politicians have tended to want finality of cases, even at the expense of certainty.

Nor have judges, cops or lawyers thought that something was seriously wrong when modern forensic systems - such as DNA, face recognition, and surveillance technology - have regularly shown here, in Britain and the US, that many old and apparently 'safe' convictions to be doubtful.

What distinguishes most such cases, is that justice was finally done only after action outside the formal criminal justice system and then only after action inside that system had failed. Fundamental flaws in police briefs had survived the scrutiny of senior investigators, prosecutors with a formal duty to be fair, experienced trial judges and learned appellate judges. Experience has repeatedly shown judges to be reluctant to look anew at old evidence, or to regard anything they thought could have been or should have been discovered before trial as fresh evidence.

And there was a steady - if declining - tendency on the part of judges to imagine that good honest policemen could never 'verbal' a defendant, withhold evidence that might support a claim of innocence, or 'brick' or 'fit up' a suspect. Those who suggested it were putting their own good characters on the line and giving prosecutors the option of telling jurors about any previous convictions they might have had. They generally assumed that scientific evidence was the detached and objective conclusions of independent experts, rather than, as shown in many cases, the partisan advocacy of tame witnesses who had taken sides.

All these weaknesses were on display in the case in which David Eastman was charged with the murder of Australian Federal Police Assistant Commissioner Colin Winchester nearly 30 years ago. These weaknesses saw Eastman convicted 24 years ago because of scientific and other evidence that did not stand up to (nor get) proper analysis. This week Eastman was found not guilty of a murder for which he spent nearly 20 years in jail for. It was not a good look for the Australian Federal Police, for the prosecution system, for an ACT judicial system which had repeatedly turned Eastman’s arguments down, and for an ACT government which was generally deaf to representations about Eastman’s innocence. Had any of these branches of government worked properly, ACT taxpayers would be tens-of-millions of dollars better off.

Colin Winchester’s murder was more than a mere murder. It was an assassination, crying for exemplary investigation. It did not want for resources. The biggest and most extensive police investigation in Australian history did not set standards anyone else would want to follow. If AFP detectives cannot get such a case right, people are entitled to wonder about the safety of more run-of-the-mill convictions.

In fact, the case showed that the AFP, the ACT, its hierarchy of courts and judges, and its politicians were not immune from the problems besetting other states and territories. Indeed, the AFP, being a smallish and rather inbred force, and the ACT, as a small city-state tended to have fewer, rather than more checks and balances than other jurisdictions. This was because so many of the players knew each other, often under different hats, and had at many times acted for or against, or in league with various of the players.

A good many of the magistrates, and even a good many of supreme court judges had at one time or another acted for David Eastman, the man accused of the murder. Two had previously been directors of public prosecutions at the time of the prosecution and had wisely disqualified themselves from matters involving him. The husband of another judge had given evidence against the man at the original trial (before his wife became a judge).

Others had been bruised (one literally) by previous encounters with Eastman, or had indicated their general view of the matter in previous hearings. They were often strangely eager (and relieved) to accede to suggestions that they disqualify themselves. Even the supply of additional judges, whether from the Federal Court or the ranks of the retired judiciary was not inexhaustible, and many soon showed themselves quick to come to conclusions and slow to see that there was often more than a molehill of genuine argument in every matter presented as a mountain by Eastman.

Almost every proposition raised in non-stop Eastman litigation was arguable, even if it did not win. Eastman was a good advocate, with a strong command of the law. His litigation was designed both to agitate fundamental matters (the safety of his conviction) and specific matter, individual points about errors in previous, lower court judicial reasoning.

For 20 years, the courts could provide no justice for Eastman.

None showed much concern about evidence of systemic police harassment of Eastman, known to be mentally unwell and to have a quick temper, in the hope that it would induce him to do or say something that could make his guilt plain. Investigators also took seriously psychiatric advice, if obtained at a distance, that Eastman was dangerous as well as unstable, and went out of their way to warn anyone with whom he associated with that they were at risk. The harassment was obvious, and publicly reported, but Eastman’s complaints, including directly to judges, were ignored.

Some of the judges believed that Eastman was constantly focused on such matters as a way of distracting from his probable guilt. Others, including the prosecutor and the first trial judge, thought that Eastman was putting on any symptoms of distress, in the hope of forcing the trial to abort. Responding to his complaints, they believe, was “playing his game”. Their determination not to be “baited” accentuated Eastman’s frustration, and made the conduct of the trial more difficult. It also heightened jury antipathy and made his conviction almost inevitable. Eastman hardly helped himself by failing to cross-examine some of the key evidence because of snits with the judge.

Rod Campbell - the late legendary Canberra Times court reporter who attended every day of a very long inquest and a six-month trial and any number of other judicial engagements - ended up concluding that a jury could have properly convicted Eastman on the evidence as presented in court, particularly after the judge’s summing up. But, he thought the prosecution case would have been a lot weaker had it been properly tested. He always had a nagging doubt.

So did Brian Martin, the retired judge from South Australia and the Northern Territory who conducted the review, who recognised that there was a strong circumstantial case against Eastman. But it left him with a nagging doubt, and he recommended that the verdict be quashed, with no retrial to follow. He found the first trial had involved a serious miscarriage of justice, even if he was reluctant to blame anyone. He was critical of police, and - in initial draft findings - scathing of the prosecution. In the final report, however, he tempered his criticism of the DPP and thought shortcomings of the prosecution, including the failure to produce exculpatory evidence to the defence, as probably accidental and unintentional.

Martin’s inquiry showed that much of the scientific evidence presented at trial was deeply flawed, primarily because of an unscientific approach, and an advocacy role, adopted by the expert imported from Victoria to examine gunshot residue. Some of his findings were untenable; some could not be replicated, and it seemed doubtful that some reported experiments had been carried out at all. It emerged that investigating police knew their expert had been dismissed from Victoria Police for scientific misconduct and the defence was not told. Police said they had told members of the prosecution staff, but none of them had any memory of this and claimed they had not known.

The defence claimed that other exculpatory material was not shown to them; prosecutors denied any policy of withholding evidence or said that if the defence sought additional material it would have been provided. In some cases, there were doubts about whether prosecutors had passed on material, because Eastman frequently changed legal representatives, and in the passage of materials from team to team, things might have gotten lost or out of order.

There were other flaws, still unexplored. The 'proof', for example, that Winchester was killed by a particular Ruger rifle said - though not proved - to be associated with Eastman, depended on spent .22 shells found at the scene. But no one proved that these had contained the bullets that killed Winchester, or even that the shells had been recently fired. The passenger seat in Winchester’s car contained boxes of ammunition he had just been given in preparation for a hunting trip in NSW.

Senior investigators, upset about the murder of a close friend, were very unprofessional in trampling over the crime scene, ignoring the pleas of the scene of crime officers. They are still in denial about its ill effects. Others made early and unwise solo searches of Winchester’s office for clues. The full litany of investigative errors or misconduct is yet to be catalogued, because the full files have not been made available to independent scrutiny. One can be sure that if no external inquiry is announced soon, that documentation of the full debacle will mysteriously disappear.

The flaw with a good deal of the overseas expert evidence, from FBI, Israeli Police and British laboratories, was that its confirmations took the form of saying that “if the tests were performed as is stated, and the findings were as stated, then the conclusions are probably right”. When one foreign expert volunteered that he suspected that the Australian expert was too much of a jack of all trades to be an expert in any of them, prosecutors helped him, and the Australian carefully recrafted their evidence to conceal any differences of opinion. The defence team was blissfully unaware, even if, according to prosecutors, they would have been given copies of the notes had they asked.

I have argued elsewhere that the police investigation was flawed by tunnel vision, and what some people call confirmation bias. There was also an all too common AFP tendency to cut corners and to be all too clever for words. It was not detached, and internal police politics determined too much of the police tactics, especially a decision to focus on Eastman at the expense of all other lines of inquiry once senior detectives developed a hunch that he was the killer.

That was a hunch which arose long before objective evidence to support it. It may have influenced the eager-to-please actions of some of the experts. From then on, the top team was looking for material which supported its conclusion or seeking to dispute, reject or ignore anything which did not support their hypothesis. It was not investigated with all the patience, professionalism, detachment, or, at the end of the day, integrity it needed.

The DPP, like his predecessors, and the AFP resisted all efforts, including by several unsuccessful judicial challenges, to have an inquiry. Neither participated in a search for the truth; both were present only to defend their reputations, usually by stonewalling. Both were very slow to produce; even slower to produce anything which showed them in a bad light. Even when it was clear that evidence the original prosecution had argued to be critical was wrong, DPP insisted that the case against Eastman, based on other bits of circumstantial evidence could still be maintained for probable conviction. He was wrong.

Having a new trial served another purpose. While anything legal was on foot, the DPP and the AFP could resist any call for an external inquiry. Neither have ever conceded any flaws in what they did. The public, or the jury, was failed the prosecution system, not the other way round it seems.

The AFP was loyal to the original investigators, with a mind closed to other possibilities. It did not re-examine its case, search for new evidence, one way or another, or use fresh forensic devices to freshen the evidence. It was take it or leave it. The jury, ultimately, was not satisfied. More than a few cops had anticipated this, but the AFP now had an alibi – that the case had foundered because of the ineptness of the lawyers, and technicalities.

The case is not suddenly ancient history, of no relevance to today or with no lessons for current AFP investigators, who are using new investigative tools, are better educated and are differently focused, particularly on terrorism. AFP culture has not undergone a fundamental change – something may manifest by the absolute reluctance of police to admit that anything was wrong. Many involved in the investigations went on to more senior positions, several to commissioner level, including in other forces.

The AFP, which at senior levels over recent decades has become dominated by an inbred self-replicating network of good old boys has never been keen on retrospection, examination of conscience or external inquiry. It is the only Australian Police Force not subjected to real external reviews since it was established 39 years ago. By now its weaknesses, idiosyncrasies and hostility to any system of accountability it cannot manipulate, outstare or ignore have become part of its DNA. Being joined with other paramilitarised agencies in the over-powerful, and under-accountable, department of home affairs will potentiate its weaknesses, not its strengths.

How sad that the history shows how poorly organised the law and the courts are in preventing serious injustices because of systemic faults in the AFP and the criminal justice system. Once the prestige of the ACT Supreme Court was among the highest in the land, with several of its members ending up as chief justices of the High Court. Its judgments are now not much cited outside the ACT. Once having the most modern technical systems in the land, it has recently opened new quarters with facilities already of a lower standard than elsewhere, unworthy both of the national capital or of a city of highly educated and fairly litigious citizens. In the incestuous ACT, too many judges and magistrates are to be seen hobnobbing with ministers, senior bureaucrats, or sitting on worthy committees with representatives of interests appearing before the courts.

Even more lamentable has been the timorousness of the ACT executive in dealing with either the brotherhood and sisterhood of ACT AFP voters, or with the senior police establishment. The AFP is highly political, with media units used to push the police barrow, and ample capacity to leak matters embarrassing to politicians. It was shown, for example, when the world became aware of police concerns about the interactions between a minister, her staff, and the CFMEU - then a target of a deeply politicised police inquiry (one which, typically, has come to nothing).

Real law reform, or investment in the justice system is not on the ALP agenda, local or federal. It might frighten the horses. Problem is, as the Winchester case shows, the horses have long bolted.

Jack Waterford is a former editor of The Canberra Times and has been involved in the Eastman case from the night of the murder, and was involved, from 1994, in arguing that the case against Eastman was flawed and that his guilt had not been established.