A lip-reader will offer expert evidence on the video recorded exchanges Bruce Lehrmann and Brittany Higgins had at a pub hours before the alleged Parliament House rape.
Justice Michael Lee ruled the expert's report admissible on Friday afternoon following opposition from Mr Lehrmann's counsel.
Earlier in the day, the judge also heard the evidence from a rape crisis counsellor and a police officer who investigated the claim.
The witnesses are some of those giving evidence in the civil proceedings brought forward by Mr Lehrmann.
Mr Lehrmann is suing Network Ten and Lisa Wilkinson over a 2021 The Project story, which did not break but first televised Ms Higgins' allegation of being raped in a ministerial office two years earlier.
The interview did not name Mr Lehrmann but he claims being identified by a number of reported details and suffering damages as a result.
Justice Lee spent the better part of the afternoon listening to legal arguments about the admissibility of the UK lip-reading expert's evidence.
The judge ultimately ruled on allowing it to be included in the trial and said he would not be "misled or confused" by it.
"It's been noted that it would be an unusual judge who's prepared to concede that a danger exists that he might be unfairly prejudiced by evidence," Justice Lee said.
"I hasten to add that my ruling allowing this evidence to be adduced is not to say that ultimately I will regard the evidence as being of great weight."
The evidence related to the previously seen audio-less CCTV from The Dock, where Mr Lehrmann and Ms Higgins drank with a group of colleagues on March 22, 2019, hours prior to the alleged rape.
Earlier in the trial, from the witness box, Mr Lehrmann denied propositions he had encouraged Ms Higgins to get drunk at the venue and said things like "all hers, all hers" regarding three drinks on a table.
"You said to her, 'drink that all now'," Matthew Collins KC, representing Ten, said to Mr Lehrmann as footage of Ms Higgins "skolling" a drink was played in court last month.
Mr Lehrmann responded: "I would completely disagree with that."
The lip-reading expert can be cross-examined on his evidence.
'She wanted her job more'
Earlier, the court heard Ms Higgins faced a "terrible conflict, a real tug of war" between reporting her alleged rape and keeping her job.
"She told me she knew if she brought this to anyone's attention she would lose her job. She was clear about that," counsellor and advocate Kathryn Cripps told the Federal Court.
Ms Cripps was called by the Canberra Rape Crisis Centre to attend Ms Higgins' first "meet and greet" with ACT Policing's sexual assault unit in April 2019.
Asked to describe her role in that meeting, which does not officially begin a case, the counsellor said she was there to advocate and be "totally supportive of her wellbeing".
Ms Cripps said Ms Higgins had been in a great deal of distress.
"She was very tearful but she tried very hard to remain composed. But there were times where she really couldn't and was in great distress," she said.
"She was flooding with tears."
The counsellor recalled Ms Higgins was especially tearful when a police officer discussed the rights of an accused person, namely they are not lawfully required to speak to police or give trial evidence.
She told the court she estimated having about 100 contacts with Ms Higgins, in the form of emails, texts, calls and face-to-face counselling sessions following the initial meeting.
In those sessions, Ms Cripps said she discovered a major reason for Ms Higgins' distress was a fear of losing her job if she officially reported her claim.
"She desperately did want to report but she felt she wanted her job more," the counsellor said.
"This total tug of war: 'I want to report but I want my job'."
Ms Cripps said the topic came up multiple times during their sessions.
"She'd only been in the ACT six months. She came for what she called, and it stands out in my memory because it was unusual, she called it her 'dream job'," she said.
Ms Higgins has previously given evidence in the trial that her job "meant everything to me".
"I loved it and I wanted to keep it," she said last week.
However, she also told barrister Steven Whybrow SC, representing Mr Lehrmann, the notion she would make up the allegation to keep her job was "insulting" because her work was "not that important".
Detective Senior Constable Sarah Harman detailed for the court the many times she chased up obtaining video recordings of Ms Higgins and Mr Lehrmann's after-hours visit to Parliament House.
"I've never encountered such pushback on obtaining CCTV. It was incredibly frustrating for me," she told the Federal Court on Friday.
The police officer said the federal agent seeking the footage on her behalf was "quarantining" the CCTV and that a lot of paperwork was required to obtain it.
The officer, who was part of the Sexual Assault and Child Abuse Team in 2019, recalled she was eventually told the CCTV footage could not be viewed until after the federal election, which had just been called.
Detective Senior Constable Harman also detailed some of her initial interactions with Ms Higgins, including being in the same meet and greet as Ms Cripps.
"She told me sexual intercourse had taken place without her consent," the officer said.
The officer described Ms Higgins' demeanour as being "articulate, coherent", but unlike the counsellor, the officer said: "She was upset but she wasn't crying."
"She did seem anxious but also willing to hear the information I gave her," she said.
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"I think she said to me she was happy to be speaking to someone about it and getting some information to make some decisions."
The court heard a running theme of the conversation between Ms Higgins and Detective Senior Constable Harman was the "replaceable nature of her job".
"She was concerned [Mr Lehrmann] was quite well connected and she had not been there very long," the officer said.
"I guess her job was replaceable, is what she seemed to suggest."
Ms Higgins would decide not to go forward with a formal police investigation at this time, instead reopening her case in early 2021.
Ten and Ms Wilkinson are calling a slate of witnesses in their defence, attempting to prove the rape allegation was substantially true and reporting it professionally was in the public interest.
Mr Lehrmann has always denied raping Ms Higgins and no findings have been made against him.
The defamation trial continues.
- Support is available for those who may be distressed. Phone Lifeline 13 11 14; Canberra Rape Crisis Centre 6247 2525.