An 11th-grader is suing his Pennsylvania school district after it allowed a transgender student to change in the boys' locker room.

It is the first case in Pennsylvania where the student filing the complaint is not himself transgender, but rather is responding to the presence of a transgender student in a sex-segregated space, according to the plaintiff's attorneys.

The plaintiff, who chose to remain anonymous, is alleging that the school district violated his constitutional right to privacy and broke sexual harassment law enshrined in Title IX when it permitted a transgender male to use the boys' locker room.

"Students from all walks of life find it deeply humiliating and offensive to be forced to share these facilities with members of the opposite sex," said Kellie Fiedorik, an attorney with the conservative group Alliance Defending Freedom and co-counsel for the plaintiff. "These voices must be heard. And today we stand for them."

The dispute arose late last year at Boyertown Area Senior High School near Pottstown, Pennsylvania.

In the fall, the plaintiff discovered a student who was born female but identifies as male using the boys' locker room before and after gym class, according to attorneys. The plaintiff complained to school administrators who told the 11th-grader that there "was nothing they could do about the situation," according to Randall Wenger chief counsel with the Independence Law Center in Harrisburg and another attorney representing the plaintiff.

"To tell someone that they need to share the locker room with somebody of the opposite sex and make it natural amounts to sexual harassment," Wenger said.

Officials from Boyertown Area School District — which straddles Montgomery and Berks counties — sent out a brief statement saying the district was "reviewing this matter with our legal counsel and has no further comment at this time."

Attorneys for the plaintiff said they filed a federal lawsuit in the U.S. District Court for the Eastern District of Pennsylvania Tuesday morning.

The case joins a growing mountain of litigation related to the rights of transgender students in public schools, an area of acute legal uncertainty.

The Alliance Defending Freedom (ADF) itself is involved in two lawsuits — one out of Illinois and another out of Minnesota — with similar claims. Co-founded by conservative Christian activist James Dobson, ADF has a long history of supporting legal causes favored by the religious right.

On the other side of the legal ledger, a number of transgender students have sued schools districts that actively prevented them from using facilities that match their gender identity. In those cases, plaintiffs claimed they had a right to use the bathroom consistent with their gender identity because any policy to the contrary would constitute sex discrimination.

In Western Pennsylvania, a transgender student sued the Pine Richland School District after it passed a policy requiring students to use the bathroom that corresponds with their biological sex.

A student in Virginia named Gavin Grimm filed a similar lawsuit. Initially the 4th U.S. Circuit Court of Appeals sided with Grimm. The case was slated to then go before the U.S. Supreme Court for a final ruling, but the high court later reversed course and sent the case back down the ladder for further review

Last year, the Obama administration sent out regulatory guidance saying school districts should allow students to use the bathroom that corresponds to their gender identity. The Trump administration later rescinded that guidance.

After that change in executive policy, the U.S. Supreme Court said the lower courts needed to take another look at the issue before it could potentially weigh in.

It's possible, however, the Boyertown case will be resolved before the high court issues a final verdict. Attorneys for the plaintiff said they would withdraw their lawsuit if the school district reverses its position and limits locker-room access on the basis of biological sex.