Arguments in a landmark trans-rights lawsuit have returned to questions of biological sex and gender identity, as three days of hearings concluded.
Roxanne Tickle is suing the Giggle for Girls app and its founder, Sall Grover, for $100,000 over alleged discrimination based on her gender identity, a Federal Court hearing was told on Thursday.
Ms Tickle is seeking an additional $100,000 for aggravated damages, based on an online campaign allegedly waged against her by Ms Grover largely on the social media platform X, formerly known as Twitter.
The court heard Ms Grover has persistently misgendered Ms Tickle in media interviews and across hundreds of posts about the case made to her roughly 93,000 online followers.
In her closing submission, Giggle's barrister Bridie Nolan labelled the figure being sought as grossly excessive, and said Ms Grover should be free to engage in political speech that may offend others.
"This case is the 'what is a woman case'," Ms Nolan told the court.
"One must be able to speak about it fearlessly and frankly."
Ms Tickle's lawyer Georgina Costello told the court her client had received an "enormous" amount of online hate as a result of Ms Grover's actions.
"The continued, deliberate misgendering of her cannot detract from the fact that she is a woman," Ms Costello argued.
Several supporters of Ms Grover travelled from interstate for the hearings, holding signs outside the courtroom stating the definition of woman to be "adult human female".
A crowdfunding campaign established to help fund Ms Grover's defence raised close to half a million dollars, the court heard.
The Giggle app was created by Ms Grover as "safe space" for women to interact with each other, free from male patterns of online violence, the court heard previously.
Ms Grover blocked Ms Tickle and refused to reinstate her based on a selfie uploaded by her to the app, which she perceived to be of a man, the court was told.
Ms Costello argued the picture was of a person presenting herself as a woman, who has undergone gender-affirming surgery and hormone treatments, told family, friends and her workplace of the decision, uses women's change rooms and shops in women's clothing departments.
Even when Ms Grover was made aware that Ms Tickle identifies as a woman and holds a female birth certificate, she refused to accept her as such, Ms Costello said during her closing submission.
She argued Ms Grover has a "modus operandi of treating transgender women as men".
"We say because of the way Ms Grover views transgender women, she was unable to see that a transgender woman is a woman," Ms Costello said.
Ms Nolan argued Ms Tickle is a man, and it was therefore lawful to exclude her from the app due to provisions in the Sex Discrimination Act.
She told Justice Robert Bromwich the court was faced with the impossible task of determining whether a person is a woman based on their "psychological state" and having undergone surgery to remove their reproductive organs.
"When a person thinks they are the woman, what are they thinking?" Ms Nolan asked.
"You cannot reduce a category in discrimination legislation to a thought."
Single-sex spaces such as women's change rooms and toilets partly exist for the purpose of women defending themselves against male violence, Ms Nolan submitted.
When a woman walks through a dark park at night and hears male footsteps behind her, "she does not stop to think, I wonder which side of Kmart this person shops on", the lawyer added.
"She laces the fingers around her keys ... she speeds up," Ms Nolan said.
If a man were to have the psychology of a woman, "they would know that, and they would not enter those spaces," she said.
Justice Bromwich will deliver judgment at a later date.
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