The Eastman inquiry has recommended David Eastmans conviction for the infamous 1989 assassination of ACT police chief Colin Stanley Winchester be quashed.
The extraordinary finding could have the convicted murderer freed after almost 19 years behind bars, should it be followed by the ACT Supreme Court.
If Eastman walks, it will be despite the inquiry's judge saying he is fairly certain the former Treasury official killed Mr Winchester.
The inquiry's report finally arrived late on Friday afternoon, after six months, thousands of pages of documents, a conveyor belt of now ageing witnesses, and countless hours of public hearings.
Its recommendations are jaw-dropping.
They could potentially clear Eastman of shooting Mr Winchester, then an Assistant Federal Police Commissioner, twice at close range outside his neighbour's Canberra home late one summer night in 1989.
Inquiry head Acting Justice Brian Martin used the 447-page report to ultimately recommend Eastmans conviction be quashed, saying a retrial would now neither be feasible nor fair.
Despite the recommendations, Acting Justice Martin said he still thought Eastman was likely to be guilty of the murder.
While I am fairly certain the applicant is guilty of the murder of the deceased, a nagging doubt remains, the judge wrote. Regardless of my view of the case and the applicants guilt, the substantial miscarriage of justice suffered by the applicant should not be allowed to stand uncorrected.
The enormity of his findings may take time to be fully realised.
The cold-blooded killing of Mr Winchester shocked the nation, sparking a lengthy manhunt, and leaving an indelible mark on the minds of Canberrans.
Mr Winchester is the highest ranking police officer ever to be assassinated, and the AFP famously described his death as the "end of innocence" in Australia.
Eastman, a disgruntled public servant trying to avoid an assault charge, quickly became a suspect in the killing and was arrested and taken to trial in 1995, following a lengthy investigation.
The ACT Government, police and prosecutors have remained tight-lipped about the inquirys findings so far, saying the matter is before the Supreme Court, which will decide on the next course of action.
Acting Justice Martin said a substantial miscarriage of justice had occurred, pointing chiefly to the unreliable gunshot residue analysis used to link Eastman to the scene.
As a consequence of the substantial miscarriage of justice, the applicant has been in custody for almost 19 years, Acting Justice Martin wrote.
Eastman, the judge said, was denied a fair chance of acquittal, and did not receive a fair trial.
He said his guilt had been decided on deeply flawed forensic evidence, in a trial where Eastman had been denied procedural fairness because of incomplete disclosure by the prosecution of all relevant material to the accuseds defence team.
The work of the cases key forensic expert, Robert Collins Barnes, was significantly undermined during the inquiry; its credibility and reliability repeatedly savaged.
Barnes, now struggling in a battle with cancer, conceded some of his evidence had been misleading, and the inquiry heard he destroyed crucial exhibits, and failed to write reports for his most important results.
Counsel assisting the inquiry, Liesl Chapman, SC, described his mixing up of results from the crime scene and Eastmans car by saying: "For a forensic scientist, it doesn't get any worse than that.
The supposedly independent expert was also covertly recorded professing himself to be a police witness, and resisting efforts to have his work reviewed.
If we don't put a brake on these turkeys ... I mean, we don't want these bastards putting that sort of stuff in writing," Mr Barnes told detectives in 1994.
Barnes was subject to an internal disciplinary investigation in Victoria at the time, and his work was later audited following concerns stemming from his evidence in a separate case.
The Eastman inquirys report lies with the ACT Supreme Court, where a full bench will decide on a way forward. The court can only use Acting Justice Martins report to aid them in their decision.
ACT Attorney General Simon Corbell said the report was "comprehensive and considered", but it would be up to the court what orders were made.
The Director of Public Prosecutions, Jon White, also declined to comment on the report, saying his office needed time to work through the detail.
The AFP also remained tight-lipped, saying it would be inappropriate to comment while the report was before the ACT Supreme Court.
Lawyers for the AFP lost a last-hour attempt to delay publication of the report on Friday afternoon.