A federal appeals court in Philadelphia handed a victory to transgender students Thursday by recognizing that allowing them to use the same restrooms and locker rooms as everyone else harms no one, and is perfectly legal.

That might sound like common sense. But to a small group of anti-LGBT extremists in Pennsylvania, it's anything but. Emboldened by the Trump administration's attacks on the transgender community, they had asked the court to do what even Trump, so far, has not: order a school district to bar its transgender students from restrooms and locker rooms they currently use.

A case about transgender students and bathrooms may not sound new. But the plaintiffs here were not transgender students. No, the challengers were non-transgender, or cisgender, students and their parents. And they objected not to exclusion, but inclusion. They claimed that their school was violating their constitutional right to bodily privacy and subjecting them to sexual harassment simply by allowing transgender students to be in restrooms and locker rooms with everyone else. That's not only novel, it turns the law on its head.

To understand the lawsuit, some background is required. Under President Barack Obama, the federal Education Department said Title IX, which prohibits sex discrimination in education, means that schools must allow transgender students to use restrooms and locker rooms that match their gender identity.

President Trump abandoned that position, but he didn't expressly tell educators to follow suit. Instead, his Education Department suggested that states and local school districts, not the federal government, should set education policy.

School districts around the country chose to stay the course. They had found that treating boys and girls who are transgender like other boys and girls was good not only for transgender students, but for schools as a whole.

One of those schools is Boyertown Area Senior High in Berks County. Recent graduate Aidan DeStefano, who is transgender, described how it felt to be allowed to use restrooms and locker rooms alongside the other boys after years of being relegated to separate facilities: "I am finally 'one of the guys,' something I have waited for my whole life."

Melissa DeStefano, left, mother of Aidan, smiles as Ria Mar, center, senior staff attorney with the ACLU, hugs Aidan DeStefano, a transgender student who recently graduated from Boyertown Area Senior High School, outside federal court in Philadelphia.
JESSICA GRIFFIN / Staff Photographer
Melissa DeStefano, left, mother of Aidan, smiles as Ria Mar, center, senior staff attorney with the ACLU, hugs Aidan DeStefano, a transgender student who recently graduated from Boyertown Area Senior High School, outside federal court in Philadelphia.

But Aidan's relief was short lived. Just weeks later, a handful of families at the school sued to try to banish Aidan and other transgender students from spaces where everyone else is welcome.

The lawsuit doesn't claim misconduct by any student of any gender. The "incidents" at issue are almost painfully mundane; one student sued because she walked into the restroom and saw another girl, who is transgender, washing her hands at the sink.

That's not to say her discomfort isn't real. Changing clothes in front of classmates of any gender can be uncomfortable. Modern educators understand this. That's why many high schools, including Boyertown's, have recently created spaces to change that truly are private, including individual stalls and curtained areas within common spaces as well as single-user restrooms. These spaces are available for any student who chooses to use them for any reason. But the students involved in the lawsuit say they do not want to change in these private areas. Instead, the lawsuit claims a constitutional right to undress in front of other students — just not students who are transgender.

That's a fundamental misinterpretation of what privacy means.

Thankfully for transgender students, the court agreed. But there's still reason to take heed: The lawsuit never uses the word "transgender." It refers to boys and girls who are transgender as members of "the opposite sex" as compared to other boys and girls. That isn't just a difference in terminology. It's an erasure of transgender people's lives.

The Boyertown case, one of half a dozen similar challenges, is the first of its kind to reach a federal court of appeals and set important precedent. But the heart of the case isn't the legal claims involved. It's the refusal to acknowledge that transgender people even exist.

Thanks to the bravery of young people, much of America now understands that they do. In a highly unusual move, the court announced its decision less than an hour after the case was argued, rejecting the challengers' claims out of hand. That sends a powerful message of recognition to transgender students in the courtroom and beyond. As former Attorney General Loretta Lynch once said to transgender people facing a similar attack: "We see you. We stand with you."

And that's something no one can erase.

Ria Tabacco Mar, a senior staff attorney with the American Civil Liberties Union,  argued the case, Doe v. Boyertown Area School District.