Brittany Higgins has questioned whether she was drugged on the night of the alleged Parliament House rape, a court has heard
An investigating police officer raised the possibility after hearing "info", the extent or content of which remains unknown, following the alleged incident.
Ms Higgins' lawyers made the submissions in documents filed to the Federal Court website on Tuesday afternoon.
Justice Michael Lee invited her to be heard one final time in the Bruce Lehrmann defamation case ahead of a highly anticipated decision.
Ms Higgins is not a party in the civil case but appeared as a principal witness for Network Ten and Lisa Wilkinson during a month-long trial last year.
She told the court she wished the civil proceedings had explored the possibility of her drugging on the night in question.
"I also have concerns from info I heard that this may have happened before or could happen again (I was referring to info that alleged victim may have been drugged)," senior AFP officer Leanne Cross wrote in her April 2019 notes.
"Paul [Sherring] - we need to speak to a range of people. Security staff cleaners may have info."
The note is said to have been written after a meeting with Senator Linda Reynolds and chief of staff Fiona Brown.
"As far as she is aware, the potential that Ms Higgins was drugged is not an issue that has been raised or explored in these proceedings," Nicholas Owens SC, representing Ms Higgins, told the Federal Court.
"In the context of a serious challenge to the honest and accuracy of Ms Higgins' account of the night in question, the potential that her perceptive and recollective abilities may have been affected other than by alcohol and trauma is an issue that she would have wished to explore."
In the submissions, Ms Higgins said if she had been a party to the proceedings, she would have interrogated a "master chronology" in which the police note was found.
Mr Owens also submitted that using credit attacks on Ms Higgins as a reason to disbelieve her rape allegation "would be to use a consequence of that rape as a basis to deny its occurence".
"Much of the conduct that Mr Lehrmann contends is dishonest is in fact entirely consistent with Ms Higgins having been rapes," he said.
"It supports, rather than undermines, her credit."
As Ms Higgins sat in the witness box and in the months since, lawyers for Mr Lehrmann have repeatedly accused her of fabricating her rape allegation, lying to several key parties, and of being motivated by self-interest.
"Ms Higgins gave powerful evidence explaining her conflicted and traumatised response in the period following her rape," Mr Owens wrote.
Mr Lehrmann is suing the network and journalist for defamation over a The Project interview which aired the allegation. A judgment is expected next Monday.
He has always denied raping Ms Higgins when the pair worked together in early 2019.
His criminal trial was aborted due to juror misconduct, with the charge of sexual intercourse without consent levelled at him later discontinued.
No criminal findings have been made against him.
A judgment in the civil case is set for Monday next week.
