The American Civil Liberties Union (ACLU) of Indiana filed a lawsuit challenging House Bill 1608.

According to the text of House Bill 1608, a school “may not provide any instruction to a student in prekindergarten through grade 3 on human sexuality.” Last month, the highly partisan bill was passed and signed into law over objections and criticism from Democrats and LGBTQ+ advocates. The bill also requires teachers to notify parents if a child requests to be called by a different name or use different pronouns.

The lawsuit claims that the law violates both the First and Fourteenth Amendments. Additionally, the lawsuit contends that the law as written is too broad and that neither “instruction” nor “human sexuality” is defined within the text.

“HEA 1608 is written so broadly that it would be next to impossible for teachers to determine what they can and cannot say to students,” said Ken Falk, ACLU of Indiana legal director. “In addition, teachers have a First Amendment right to express themselves as private citizens outside of the classroom, including in the school’s hallways, playground, or before and after school, but the vagueness of this law would certainly have a chilling effect on those rights.”

The ACLU filed the lawsuit on behalf of Kayla Smiley, an Indianapolis Public Schools teacher. According to the lawsuit, several books in her classroom library contain age-appropriate books on LGBTQ+ issues. She questions if material like the biographies of Harvey Milk and Elton John would qualify as “instruction on human sexuality.” It is also suggested that redirecting a student about using the term “gay” as a pejorative could violate the law.

The lawsuit, which names Katie Jenner, Indiana’s secretary of education, as the defendant, is seeking an injunction to halt the implementation of the “human sexuality” instruction provision. The provision takes effect on July 1.

Many other red states around the country have passed similar laws. Republicans have zeroed in on curriculum and instructional material that discuss gender and sexuality. In response, the U.S. Department of Education announced that it was creating a coordinator to combat book bans along those lines.

This is the second such lawsuit the ACLU of Indiana filed this year. Back in April, they also filed a lawsuit on behalf of transgender youth regarding Senate Bill 480, which limits gender-affirming care.