BALTIMORE (AP) — A federal judge in Maryland has denied an effort by President Donald J. Trump’s administration to shield information it used to implement a ban on transgender people in the military.

The American Civil Liberties Union sued the administration on behalf of a dozen transgender people who are currently serving or want to serve in the armed forces.

U.S. Magistrate Judge A. David Copperthite ruled Tuesday that the documents are relevant to the administration’s intent. He says whether the ban was for military purposes or for purely political and discriminatory purposes “is at the very heart of this litigation.”

The ACLU contends the ban violates the constitutional guarantees of equal protection and substantive due process by singling out transgender individuals for unequal and discriminatory treatment. The lawsuit was filed last year.