PIERRE, S.D. — South Dakota’s governor vetoed a bill Tuesday that would have made the state the first in the U.S. to approve a law requiring transgender students to use bathrooms and locker rooms that match their sex at birth.

South Dakota would have been the first state to take such a step. But Republican Gov. Dennis Daugaard rejected the bill after the American Civil Liberties Union, the Human Rights Campaign and transgender students and adults called the legislation discriminatory.

In his veto message, Daugaard wrote that the bill “does not address any pressing issue” and that such decisions were best left to local school officials. The Republican-controlled Legislature approved the proposal last month, with supporters saying it was meant to protect student privacy.

Transgender rights are a new flashpoint in national culture fights following the landmark U.S. Supreme Court ruling that legalized same-sex marriage last year. That victory encouraged advocates for lesbian, gay, bisexual and transgender rights to push harder, prompting conservative backlash.

Caitlyn Jenner, the transgender activist and former Olympic decathlon gold medalist, had called on Daugaard to veto the bill.

Other high-profile cases include last week’s vote in North Carolina by the Charlotte City Council to allow transgender people to choose a bathroom. The vote was criticized by Gov. Pat McCrory, who said it denied privacy rights for those who expect to share restrooms or locker rooms only with people born with the same anatomy.

In Texas, Houston voters soundly defeated an ordinance that would have banned discrimination against transgender people after opponents alleged it would allow sexual predators to go into women’s bathrooms.

Opponents called the legislation an attack on vulnerable transgender students that would further marginalize them at school.