Melissa and Ash Whitaker, a transgender boy who sued to protect his civil rights at a Wisconsin public school. (Transgender Law Center)

BECAUSE ASH WHITAKER is set to graduate from his high school on Saturday, it might seem that this week’s federal appeals court decision allowing him to use the school bathroom that aligns with his gender identity came too late to give him much benefit. Not so. The 17-year-old honors student will be able to walk across that stage knowing not only that he got the justice he asked for, but also that his case may prove pivotal in securing protections against discrimination for all transgender Americans.

The U.S. Court of Appeals for the 7th Circuit ruled Tuesday that Kenosha Unified School District No. 1 in Wisconsin violated the transgender student’s civil rights by refusing to let him use the boys’ bathroom. The unanimous ruling by a three-judge panel upheld a preliminary injunction granted by a lower court giving him access to the boys’ restrooms while his case is being tried. Mr. Whitaker was likely to win, the panel determined. Most significantly, the court’s sweeping finding held that his rights were violated under the 14th Amendment of the Constitution and Title IX prohibitions against sex discrimination in federally funded schools.

Similar reasoning was the basis for a legal guidance issued to schools last year by the Obama administration affirming protections for transgender students, including the right to use school restrooms and locker rooms that conformed with their gender identity. It sparked a backlash from critics who called it federal overreach, and the Trump administration was quick to rescind it, arguing that how transgender students are treated should be left to state and local decision-makers. The move prompted the Supreme Court not to hear scheduled arguments in a case (of Virginia student Gavin Grimm) in which the guidance was a major factor. The 7th Circuit decision, without mentioning the guidance, bears out the contention of Obama officials that they were not making new law but rather enforcing existing law. Ultimately the issue will be decided by the Supreme Court.

The 7th Circuit ruling powerfully spells out what is at stake: the harm that can be done to children as they come to grips with their gender identity and the needless cruelty of policies that stigmatize them. Mr. Whitaker was ranked within the top 5 percent of his class and was involved in a number of extracurricular activities, including orchestra, theater, tennis and the Astronomical Society. His transition to a boy had been accepted by much of the school community. That he had used the boys’ bathroom without incident or complaint for six months seemed not to matter to those charged with supporting and encouraging students.

The school’s efforts against him — including having him followed around to enforce where he went to the bathroom — led Mr. Whitaker to depression and thoughts of suicide. Toward what end? There was never any evidence of any other students’ privacy being infringed upon, and as Judge Ann Claire Williams wrote, “common sense tells us that the communal restroom is a place where individuals act in a discreet manner to protect their privacy and those who have true privacy concerns are able to utilize a stall.”

Congratulations to Mr. Whitaker for persevering.