Demand is growing for the urgent release of a leaked report into how the justice system handled Brittany Higgins’ rape allegation.

An independent inquiry report on the sexual assault trial of Bruce Lehrmann has not been publicly released, but several media outlets have published some of the findings.

The head of the Australian Federal Police Association said media reports of the investigation’s findings vindicated his officers.

“While we welcomed the inquiry, we knew it would be the only way to reveal the truth,” Alex Caruana said on Thursday.

“We were always confident that the investigating officers had conducted a thorough and professional investigation from day one.”

The police union said the report should immediately be released in full, describing it as a welfare issue for everyone involved.

Mr Caruana said the government should consider investigating who leaked the report.

“Sexual assault investigations are among the hardest to conduct, even more so when you have a high level of national scrutiny,” he said.

The independent inquiry headed by former Supreme Court judge Walter Sofronoff delivered its report to the ACT government on July 31.

Despite the media leaks, the territory government has refused to release the report and maintained it would be considered by cabinet first.

“The report and the ACT government response will be released publicly once this process has been finalised and it will be tabled in the Legislative Assembly at the end of the month,” a spokesperson told AAP.

Mr Sofronoff declined to comment when contacted by AAP.

ACT Liberal leader Elizabeth Lee said there was no justification for Chief Minister Andrew Barr to keep the report under wraps. 

“Given the extensive media coverage that this report and inquiry have both had over the past 24 hours, it is essential that the report be released in full, immediately, to ensure that there are no undue aspersions – unfounded or otherwise – on any parties that are involved,” she said.

“Andrew Barr and (Attorney-General) Shane Rattenbury must demonstrate leadership and ministerial responsibility for these findings.” 

While investigating officers have been absolved of blame, the report is expected to include negative findings against ACT chief prosecutor Shane Drumgold.

Mr Drumgold has taken leave until the end of this month while the government considers the findings.

He told the inquiry he believed police had a “passion” for the prosecution to fail, based on a series of “strange events” during the investigation and trial.

Yet after calling for an inquiry on this basis, Mr Drumgold conceded his original belief might actually have been a “skills deficit” on the part of police. 

The inquiry revealed confusion within the police force about when to charge a suspect.

Australian Federal Police Detective Superintendent Scott Moller, who led the investigation, described the intense pressure from the public, media and within the AFP to lay a charge against Mr Lehrmann, despite some officers believing the evidence wasn’t strong enough to do so.

Mr Lehrmann was accused of raping Ms Higgins at Parliament House after a night out in 2019 but denies the allegation.

Prosecutors dropped the charge against Mr Lehrmann over fears about the impact of a second trial on Ms Higgins’ mental health.

The first trial was aborted due to juror misconduct.

Mr Lehrmann wrote on his Instagram account the report had revealed what he and his legal team suspected.

“This is overwhelming and alarming reading,” he said. 

“It is a credit to Mr Sofronoff and his team for pulling back the covers and exposing what really is a dark chapter for the ACT justice system.”

By Paul Osborne in Canberra

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