Conservative Legal Movement Uses 'Biological Sex' Rhetoric in Trans Rights Cases to Undermine RBG's Sex-Discrimination Jurisprudence
Source: Reva Siegel, Mary Ziegler. "Conservatives are trying to use a Trojan horse to kill RBG’s biggest legacy.." August 7, 2026. slate.com
The Gist
The authors argue that when the Supreme Court ruled that states could ban transgender athletes from women's sports by claiming it was just about 'biological sex,' this wasn't really about sports—it's part of a bigger conservative legal strategy to weaken the entire body of laws protecting people from sex discrimination. They point to evidence that conservative groups are already using this same 'biological differences' language to attack Title IX's protections for women's sports funding more broadly, revealing the trans athlete ruling was just the opening move.
Conclusion
The Supreme Court's use of 'biological sex' reasoning in trans-rights cases like B.P.J. is a Trojan horse strategy being used by the conservative legal movement to dismantle the broader sex-discrimination legal framework established by Ruth Bader Ginsburg, not merely to resolve narrow questions about transgender rights.
Premises
- In B.P.J., the Supreme Court framed West Virginia's ban on trans athletes as simply 'recognizing physical differences between the sexes,' treating biological sex as self-evidently justifying sex-based discrimination without scrutiny for sex-role stereotyping
- The term 'biological sex' appears nowhere in Title IX's text or legislative history, and was first introduced into the statute's discourse in 2016 by conservative lawmakers seeking to redefine 'sex'—showing the Court's framing is a modern conservative construct, not historical fact
- Title IX was actually enacted to combat sex discrimination and stereotyping (e.g., justifications that women's sports funding disparities were due to fears about infertility or poor competitiveness), not to enforce biological differences
- The concept of 'biological sex' has a dual character: it appears scientific but is also used by religious/traditionalist movements (e.g., the Nashville Statement) to justify broader claims about gender roles, marriage, and traditional morality
- Shortly after B.P.J., the Heritage Foundation released a report using similar 'natural differences' rhetoric to argue for gutting Title IX's equal-funding requirements entirely, revealing the broader agenda behind the rhetoric
- The author of that Heritage report has called for reversing landmark sex-discrimination cases and has spoken against women's suffrage, indicating the movement's ambitions extend far beyond the trans athlete issue
- The Court in B.P.J. quoted language from United States v. Virginia (Ginsburg's foundational sex-equality opinion) about 'enduring' physical differences—language cherry-picked by ADF—suggesting a deliberate strategy to redirect that precedent's authority toward undermining sex-equality protections rather than upholding them
Assumptions
- Legal reasoning that emphasizes biological/physical differences between sexes tends to reduce judicial scrutiny of sex-based classifications, making it easier to justify discriminatory laws
- The intentions and rhetoric of ideologically-aligned advocacy groups (ADF, Heritage Foundation) can be used to infer the trajectory or purpose of judicial reasoning, even when judges don't explicitly state such purposes
- Historical intent (Title IX's original purpose) is significant for interpreting how a statute should be applied today, and current reinterpretation constitutes a meaningful departure from that intent
- A ruling on a narrow issue (trans athletes) can be read as a strategic first step toward dismantling broader legal doctrine, similar to how Dobbs case may have functioned in the abortion context
- The authors assume that recognizing biological differences necessarily conflicts with anti-stereotyping principles, rather than being potentially reconcilable in some contexts