Police 'had a passion' for Lehrmann prosecution to fail

Prosecutors in former Liberal staffer Bruce Lehrmann's rape trial "closed ranks" against police because of their concerns over the conduct of some officers during the investigation.  

ACT Director of Public Prosecutions Shane Drumgold provided a third day of evidence to an independent inquiry into how the territory's justice system handled rape allegations made by Mr Lehrmann's ex-colleague Brittany Higgins.

Mr Lehrmann faced an ACT Supreme Court trial in October 2022 but juror misconduct meant a verdict was not reached.

Mr Drumgold said there was "unprecedented pressure" on his office not to proceed with a retrial.

He said this was part of the reason he wrote to the chief police officer after the first trial was vacated requesting a public inquiry into police interference in the criminal justice process. 

"Police had a passion for this prosecution to fail, that was my observation," he told the inquiry on Wednesday.

"I felt that there was enough evidence to justify an inquiry into it."

Mr Drumgold said his office had "very little communication" with police officers during the October trial.

"We had definitely closed ranks because we were quite confident that the police had lost objectivity in the matter," he said. 

Prosecutors ultimately dropped the charge against Mr Lehrmann due to concerns about the impact of a second trial on Ms Higgins' mental health. 

Mr Drumgold earlier said a decision by police to conduct a second interview with Ms Higgins was "irregular" in a sexual assault investigation.  

"I held concerns because a subsequent interview would be traumatic to a complainant (and) my position was that if there was an inconsistency it should be left to the defence," he said.

"The (police) evidence-in-chief interview looked like a cross examination. It looked like a defence cross-examination."

Mr Drumgold said he held separate concerns about the motivations of some police officers when communicating with Mr Lehrmann's defence team.

"My concern was (police) going to great lengths to feed inaccurate information, inaccurate assessment of information, in the hope of derailing the case," he said.

His concern was shared by a deputy commissioner in the ACT Police, who warned her officers against speaking with Mr Lehrmann's lawyers.

Mr Drumgold has previously given evidence that police investigating the allegations tried to convince him not to charge Mr Lehrmann in the first place. 

Asked whether his assessments of police conduct during the case affected his own ability to be objective, Mr Drumgold said no.

The ACT government established the inquiry after accusations by police and prosecutors about each other's conduct during the case.

Former Queensland solicitor-general Walter Sofronoff is leading the inquiry which is examining how territory police, prosecutors and a victim support service handled Ms Higgins' allegations.