100 groups warn ‘biological sex’ push would strip protections from trans and intersex Australians
100 organisations urge MPs, including Liberal Senator Michaelia Cash, to reject ‘biological sex’ rewrite of Sex Discrimination Act. (Getty Images)
A coalition of 100 organisations has written to federal MPs urging them to reject any move to redefine “sex” in Australia’s Sex Discrimination Act, warning it would undermine protections for trans and intersex people and weaken safeguards for women.
In an open letter, the signatories, spanning women’s organisations, LGBTIQ+ groups, unions, disability groups and mental health advocates, said rewriting the definition would have wide-ranging consequences: “[It] would strip protections from transgender Australians and weaken safeguards for women more broadly. It would render entire groups of people invisible in law and trigger a cascade of damaging consequences.”
The letter also rejected claims that trans inclusion undermines women’s rights, adding: “For decades, Australian governments have recognised transgender people in law and allowed amendments to identity documents. These protections have coexisted with women’s rights without evidence of safety issues or systemic failures.”
Organisations listed as signatories included ACOSS, ACON, Equality Australia, Women With Disabilities Australia and Women’s Legal Services Australia.
What changes are being pushed?
The intervention follows a second Senate defeat last week for a Coalition bill seeking to rewrite the Sex Discrimination Act.
A motion to return Liberal Senator Michaelia Cash’s Sex Discrimination Amendment (Restoring Common Sense and Recognising Biological Sex) Bill 2026 to Parliament’s agenda was defeated 32 votes to 22.
The open letter urged MPs to reject changes that would redefine “sex” in the Act or remove gender identity as a protected attribute.
It warned that such reforms ignore the reality of people born with variations of sex characteristics and could lead to increased scrutiny of bodies and appearances in workplaces, schools, and when accessing everyday services and facilities.
Dr Morgan Carpenter, executive director of Intersex Human Rights Australia, said: “Proposals to define biological sex in law don’t respect people whose innate characteristics are not typically female or typically male. These proposals coercively reassign many of us to categories we’ve never lived in.”
What are advocates and politicians saying?
Equality Australia, a national advocacy group campaigning for LGBTQ+ equality in Australian law and policy, has been among the organisations warning against the proposed changes.
Its CEO Anna Brown said: “Changing the meaning of ‘sex’ in the SDA doesn’t solve a problem – it creates one.”
Cash said in a Senator Michaelia Cash Instagram reel that she would continue campaigning for changes to the legislation.
Greens Senator Nick McKim described the push as “transphobic”, saying: “They are hunting for votes by hunting vulnerable people,” and accusing proponents of “dangerously transphobic legislation which targets trans people and deliberately exposes them to harm.”
The Sex Discrimination Act has also been central to recent legal fights over gender identity protections. In August 2024, a court determined that a women-only app had unlawfully discriminated against a trans woman under the Act, in the first Federal Court case to weigh in on gender identity discrimination.
