The U.S. Supreme Court on Friday said it would take up a case involving the hot button issue of transgender rights, a surprising move given the court's usual go-slow approach on controversial questions.

A school district in rural Virginia is urging the justices to rule that it cannot be ordered to let transgender students use bathrooms that match their gender identities.

The court's decision will also affect the legal battle over transgender rights in North Carolina, where the state's economy is suffering from boycotts in response to the bathroom law it adopted in March.

The school board in Gloucester County, on the Chesapeake Bay, is appealing a court order involving a high school senior, Gavin Grimm. Grimm was born female but began to identify as male after his freshman year. He legally changed his name and began hormone therapy.

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The principal gave him permission to use the boys' bathroom, but the school board adopted a policy saying restrooms were "limited to the corresponding biological genders." Grimm and other transgender students were to be provided single-occupant restrooms, it said.

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Grimm sued, claiming that the arrangement made him feel stigmatized and isolated, and a federal court ruled in his favor.

The Fourth Circuit Court of Appeals in Richmond, Virginia ruled that refusing to allow students to use bathrooms corresponding to their gender identity would violate a federal law known as Title IX that bans sex discrimination by schools receiving federal funds.

The ruling cited an Education Department letter that said "a school generally must treat transgender students consistent with their gender identity." The appeals court found that to be a reasonable interpretation of Title IX.

It was the first such decision of its kind, and the Obama administration cited the ruling in its transgender lawsuit against North Carolina and in a letter commending the policy to all the nation's schools.

In August, the Supreme Court put the ruling on hold while considering whether to take the Gloucester County case. That hold will continue until the justices reach a decision next spring. In the meantime, Grimm will be prohibited from using the boys' restroom.

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The school district argues that when Title IX was adopted more than 40 years ago, no one thought the term "sex" meant anything other than the physical characteristics assigned at birth.

If instead it means "one's internal sense of maleness or femaleness, the whole concept of permissible sex-separation collapses. What sense could there be in allowing separate facilities for the different sexes if a biological male could legally qualify as a woman based merely on his subjective perception of being one?" the school board asks.

Grimm, represented by the ACLU, says the term encompasses all aspects of sex, both physical and behavioral.

Interpreting Title IX to allow him to use the boys' restroom is "no more novel than an interpretation placing him in the girls' restroom. What is novel is the existence of transgender students who are finally able to live consistently with their gender identity," the ACLU says.

The court has not yet set a date for oral argument, but the case will not be heard until January at the earliest.