Giving evidence on Thursday in a Federal Court defamation trial, Ms Higgins became emotional during her cross-examination by Lehrmann's barrister Steven Whybrow SC.
"That is a fabrication that you were sexually assaulted," Mr Whybrow said.
"I understand that is your assertion. It's insulting but I understand it," Ms Higgins replied.
Lehrmann has sued Network Ten and journalist Lisa Wilkinson for defamation over a February 2021 report on The Project where Ms Higgins was interviewed.
The rape allegedly occurred in the Parliament House office of Lehrmann and Ms Higgins' then boss, senator Linda Reynolds, in the early hours of March 23, 2019.
Lehrmann denies that any sexual intercourse or intimacy occurred.
Bruce Lehrmann denies claims by Brittany Higgins of sexual assault in a Parliament House office. (Dean Lewins/AAP PHOTOS)
Mr Whybrow's lengthy questioning revolved around how Ms Higgins' evidence had changed over time between statements she gave to the police, in court, to journalists from Ten and News.com.au and in a first draft of a book she had sent to publisher Penguin Random House.
One example was that the location of a box of chocolates eaten after the alleged rape had changed between versions.
"I want to suggest to you that is an example of your evidence evolving as you find out new information," Mr Whybrow said.
"No, I don't accept that," Ms Higgins answered.
She admitted giving incorrect statements to Wilkinson and Ten producer Angus Llewellyn during a five-hour interview conducted in January 2021, before she was filmed for The Project broadcast.
These claims, which included what security did and what she was wearing after the alleged rape, were based on her beliefs at the time, the court was told.
Ms Higgins was also taken to her $325,000 book deal with Penguin Random House for an account of the events surrounding the alleged rape.
Already receiving around $108,000 as an advance, Ms Higgins denied she had a financial interest in the outcome of the defamation proceedings, given that she was still yet to receive approximately $216,000.
"If I ever actually finish the book, I will donate all $200,000 whatever to charity. I don't care about the money," she told Justice Michael Lee.
Ms Higgins said a draft sent to Penguin in April 2021 was "crap" and contained inaccuracies about the alleged rape, saying her evidence to the court was the actual truth.
Lisa Wilkinson and Network Ten are being sued for defamation by ex-Liberal staffer Bruce Lehrmann. (Dean Lewins/AAP PHOTOS)
The defamation trial, which was watched by almost 15,000 people on a livestream, continues.
Lehrmann has already given evidence in which he admitted to a number of lies and false statements he gave to police, Parliament House security, his employer and supervisor, and the media.
He was charged in August 2021 over the alleged rape, but his criminal trial in the ACT Supreme Court was derailed by juror misconduct.
Prosecutors did not seek a second trial, citing concerns for Ms Higgins' mental health.
A landmark report into the ACT legal system and the Higgins case in August made damning findings against former director of public prosecutions Shane Drumgold, which he has sought to challenge.
Lehrmann is also before Queensland courts accused of raping another woman twice in Toowoomba in October 2021.
He has not yet entered a plea, but his lawyers have indicated he denies the charges.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
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