Transgender students once found an ally in the Department of Education, which under the Obama administration robustly investigated alleged violations of their civil rights and argued that federal laws against sex discrimination ensured their access to public school bathrooms and changing facilities.

But that has changed in the months since President Trump took office. Since February, the department and its Office of Civil Rights have reversed their position on bathroom access and rescinded the findings of at least one civil rights investigation. Advocacy groups say the two have also made confusing statements about discrimination against gay and transgender students.

This quick erosion of support has reinforced the importance of the court system for transgender students, many advocates said. But, paradoxically, it has also made it harder for such students to pursue civil rights claims.

“Students and their families have a right to go to court to have their rights vindicated, but they shouldn’t have to,” said Harper Jean Tobin, the policy director of the National Center for Transgender Equality. “The Office of Civil Rights is tasked with handling these complaints precisely to avoid costly and time-consuming litigation, but if it refuses to do it’s job, the courts will be the backstop.”