Tennessee Gov. Lee signed SB1440 defining 'sex' as immutable at birth, ending gender-marker updates on state IDs

On May 24, 2023, Tennessee Governor Bill Lee signed SB1440 into law as Public Chapter 486, adding a statutory definition of "sex" to Tennessee Code Annotated. The act, passed by the 113th General Assembly (Senate 27-6 on March 13 and House 71-21 on April 21), defines "sex" throughout state code as "a person's immutable biological sex as determined by anatomy and genetics existing at the time of birth," and specifies that evidence of a person's biological sex includes government-issued identification matching the person's original birth certificate. Codified at TCA sections 1-3-105(c) and 49-2-802(4), the law took effect July 1, 2023.

Although the statute contained no enforcement or penalty provision, the Tennessee Department of Safety used the new definition to change administrative practice: it stopped updating the gender marker on driver's licenses for transgender residents, ending a previously available path to accurate state identification. The definitional mechanism alone was used to withdraw legal recognition of gender transition on state-issued IDs, tying a person's recognized sex to an unamendable birth record.

Updates

2024-04-23 — ACLU-TN filed lawsuit challenging driver license gender-marker rule [3]

The ACLU of Tennessee filed suit in federal court on behalf of transgender Tennesseans denied gender-marker updates on their driver's licenses under the new "sex" definition, seeking to strike down the Department of Safety's implementing rule.

2025-05-12 — ACLU-TN moved to block driver license rule pending litigation [4]

The ACLU of Tennessee asked the court for a preliminary injunction halting enforcement of the driver's-license gender-marker rule while the underlying lawsuit proceeds.