Despite the acquittal, Burke's long career was irreparably tainted by the allegations and he retired last September with what is understood to be a significant severance deal bound by confidentiality.
Today, the Independent Police Conduct Authority released its conclusions into two separate aspects of the case; the sexual allegations against Burke himself and his wider conduct, as well as how the police inquiry team treated the first complainant.
The IPCA says it cannot publicly release the full report into the allegations against Burke because of suppression orders put in place during the High Court trial.
But even weighing the prosecution case against Burke on a "balance of probabilities" standard of proof, which is a lower threshold than "beyond reasonable doubt" in a criminal trial, the IPCA found there was "insufficient cogent evidence" to conclude Burke sexually assaulted either complainant.
When assessing evidence, the Authority was cognisant of the time elapsed since the alleged events and the recounting of those events to Police, then to the Authority and finally in court, said Judge Colin Doherty, the chair of the IPCA.
"This affected the reliability of the evidence proffered. In some cases, the Authority could not make firm findings on the available evidence."
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However, Judge Doherty did conclude that some aspects of Burke's conduct represented poor judgment; or were wrong in principle despite meeting the acceptable professional standards of the time.
The first complainant, referred to as Ms X by the IPCA, was a woman in her 20s in a violent relationship with a notorious criminal. She was stabbed by her partner and first met Burke as the officer investigating the serious assault.
"I thought [Burke] was awesome. He was my hero," she said at the High Court trial.
She made several sexual allegations against Burke, all of which he denied.
The second complainant was of a similar age to Burke, in his 40s at the time, who she spoke to about her dealings with a fraudster the detective was investigating in 2002.
She claimed Burke came to her house, uninvited, with a box of beers and a bottle of wine.
After talking for several hours, the woman said she thought Burke was too drunk to drive and offered him a bed in the spare room.
She accused him of sexually assaulting her, while Burke said the liaison was consensual.
At the time of his contact with both women, the IPCA said Burke was an experienced and competent officer while both complainants were vulnerable in their own way.
"The power imbalance between the parties was central to the Authority's assessment," said Judge Doherty of the finding of Burke's poor judgment.
However, the judge noted Burke's conduct towards the first complainant was in line with "good" investigative practice at the time, although in principle it was inappropriate.
Burke told the Herald he was reviewing the findings of the IPCA report and would comment at a later date.
In a second report released today, the IPCA reviewed a number of issues raised by the first woman to lay a formal complaint against Burke, referred to as Ms X, largely around poor communication by the investigation team dealing with her.
One of the specific complaints to the IPCA was that the police disclosed information about her case, including details she was unaware of, to a third party without her consent.
The third party was a support person contracted to the Ministry of Justice, whom the police suggested Ms X should liaise with instead of her own support person.
Ms X also believed the police were protecting Burke by not speaking to the second complainant, Ms Y, for several months after Ms X gave them her contact details.
And to establish contact with Ms X's mother, after several failed attempts because the police had incorrectly recorded her phone number, detectives sent an email to her mother's work email and copied it to her supervisor. The manager questioned Ms X's mother about this, which distressed her.
These instances eroded Ms X's trust and confidence in the police investigation team, headed by Detective Inspector Darryl Sweeney from Canterbury, and made her believe her complaint was not treated seriously.
However, despite her concerns, the IPCA found the police conducted a fair and thorough investigation of her complaint.
Failing to contact Ms Y in a timely manner was the result of a "regrettable breakdown in communication", not a deliberate attempt to protect Burke, said the IPCA, while the email to Ms X's mother was "well motivated and not unreasonable in the circumstances".
The IPCA noted the investigation team allowed Ms X to believe they were able to provide her with a level of service, in terms of communication and progress, that was unachievable.
When the relationship broke down, the IPCA said it was a credit to police that repeated efforts were made to repair the damage with Ms X and her support person.
In response to the IPCA report, the complainant Ms X told the Herald she believed the police were not "victim focused" in dealing with her and the number of communication errors "destroyed any trust I had left in Police".
In a written statement, Assistant Commissioner Richard Chambers said suppression orders and privacy considerations limit what the police can say in response to the IPCA reports but he acknowledged the efforts of the officers who worked on the investigation.
"Police treat any allegations involving the conduct of a Police officer extremely seriously. After police became aware of the complaints, staff from a different part of the country were brought in for the investigation to avoid any conflict of interest.
"These officers did an excellent job of investigating a complex, sensitive and historical case. They were focused on the wellbeing of the complainants and provided as much ongoing support as possible throughout the investigation process.
"Any sexual assault case will always be treated by our staff with the utmost respect, professionalism and empathy. Of course there can always be learnings for our officers and our organisation and we accept that.
"Police's role was to put the best available evidence before the Courts to enable it to reach a decision."
