The US Court of Appeals for the Eighth Circuit reinstated an Iowa law on Friday that requires public school libraries to remove books that are not “age appropriate,” such as when they describe or depict “sex acts.” The law, SF 496, also forbids education about gender identity. A federal district judge previously enjoined those provisions, blocking their enforcement.

The appeals court vacated the district judge’s decision because he did not apply the correct analysis for facial challenges, which seek to block a law in all its applications, rather than as applied to the plaintiff. However, the plaintiffs in this case, which include an LGBT advocacy group, students, and teachers, may again request an injunction in the district court.

Yet, the appeals court noted that states, in defining public schools’ “pedagogical mission,” may limit expression, including what books libraries offer. The court added that judges ruling on such limitations should “bear in mind that Iowa is not required to tolerate speech that undermines or is inconsistent with its central mission of educating Iowa Children.”

Iowa Governor Kim Reynolds (R) celebrated the decision. She stressed that “it should be parents who decide when and if sexually explicit books are appropriate for their children.” Iowa Attorney General Brenna Bird also called the decision a victory.

The American Civil Liberties Union (ACLU), counsel for the plaintiffs, lamented that the law will now “take effect just before students go back to school.” But the organization also expressed hope, noting that the court rejected Iowa’s “most dangerous arguments” and that the plaintiffs will try to block the law again “at the earliest opportunity.”

Hot-button Iowa legislation has faced litigation in recent months. In July, a federal judge upheld the state’s six-week abortion ban. In May, civil rights groups sued to stop a criminal immigration law from going into effect. And in previous years, litigation ensued over the state’s limits on damages for victims of police brutality and mask-mandate bans.

Book bans over sexual or gender identity-related content are not unique to Iowa. A federal appellate court granted plaintiffs a victory in their challenge to Texas’s book ban. A district judge did the same in Arkansas. And Alabama and Idaho are considering similar bills, potentially giving rise to more litigation in the future.