Ms Higgins is fighting her former boss Senator Linda Reynolds over a series of social media posts from 2023 that the ex-defence minister believes damaged her reputation.
The senator's lawyer Martin Bennett told a Perth court a statement purporting to be Ms Higgins', that her lawyer Rachael Young read during her closing submissions, was not written by her.
A court has been told that a speech by Brittany Higgins was edited by Sky News anchor Peta Credlin. (Richard Wainwright/AAP PHOTOS)
"It wasn't Ms Higgins' voice at all," he told the Western Australian Supreme Court on Tuesday in reference to the statement from February 19, 2021.
"The draft ... was prepared by (Ms Higgins' now-husband David) Sharaz and it was edited by Peta Credlin."
Mr Bennett read out a series of messages between Mr Sharaz and Ms Credlin in which he said: "Thank you again for your help. Please see below the initial draft, feel free to completely re-work wherever you see fit".
Mr Bennett said Ms Credlin - former prime minister Tony Abbott's chief of staff - provided suggestions to rework paragraphs, asking Mr Sharaz to call her so she could talk him through the changes.
He also said Mr Sharaz sent the edited document to journalist Lisa Wilkinson.
"This idea that statements made by Ms Higgins after the date of The Project interview and the (News.com.au reporter Samantha) Maiden article corroborate her motive in making those statements ... needs to be treated with caution because what appears to be Ms Higgins' voice was the voice of people jumping on a bandwagon,' Mr Bennett said.
Ms Young finished her closing argument for Ms Higgins' defence by saying the senator had repeatedly stated she was protecting Ms Higgins' agency in defence of her handling of the alleged rape.
"But Ms Higgins had no agency when she was raped in March 2019 on the couch in Senator Reynolds' private office," she said.
Ms Young read an extract from Ms Higgins' statement in which she said she had re-engaged with the Australian Federal Police and would proceed with a formal complaint over her alleged rape.
In it, Ms Higgins also said: "The prime minister has repeatedly told the parliament that I should be given agency going forward".
"I don't believe that agency was provided to me over the past two years but I seize it now and have advised the Prime Minister's Office that I expect a voice in framing the scope and terms of reference for a new and significant review into the conditions for all ministerial and parliamentary staff.
"From the outset, I have been driven by my desire to ensure that no other person would have to go through the trauma that I experienced during my time in parliament house.
"I was failed repeatedly, but I now have my voice, and I am determined to use it ensure that this is never allowed to happen to another member of staff again."
The trial continues on Wednesday when Mr Bennett is scheduled to complete his closing remarks.
