An LGBT activist group is suing the federal government over documents relating to President Eisenhower’s 1953 executive order on “sexual perversion” that led to the firing of thousands of federal employees for being gay.

The Mattachine Society of Washington D.C, one of the first gay rights groups in America, wrote in a lawsuit filed earlier this week that the Department of Justice has taken more than three years to fulfill a Freedom of Information Act request made by the group that seeks “all files in the FBI’s possession created by and communications to and from Chief Justice Warren Burger concerning” what they call the “purge” of gay federal employees.

“Our federal government owes it to the thousands of men and women whose careers were destroyed to come clean and produce these records now. Justice demands it,” Mattachine Society of Washington, DC President Charles Francis said.

The group said the feds have identified the requested documents but have refused to turn them over, citing a “deliberative process privilege” for documents sent between DOJ and the FBI.

According to the Mattachine Society, it’s estimated that as many as 10,000 federal employees were fired for homosexuality in the 1950s as a result of Eisenhower’s order. Other estimates put the number at 5,000. Former Supreme Court Chief Justice Warren Burger, then an assistant attorney general, was tasked with carrying out the order.

Eisenhower’s order came at a time when Senator Joseph McCarthy was whipping America into a frenzy over suspected communist operatives working in the federal government, Hollywood and elsewhere. In 1950, the chairman of the Republican National Committee, Guy George Gabrielson, said that “sexual perverts who have infiltrated our Government in recent years” were “perhaps as dangerous as the actual Communists.” Soon, McCarthy’s communist witch hunts included alleged “homosexuals” too. In his book about McCarthy, former Senator Alan Simpson described the homosexual witch hunts—which later became known as the “Lavender Scare”—as having “harmed far more people” than his targeting of suspected communists.

In its complaint, the Mattachine Society states that Eisenhower, “with the stroke of a pen, provided J. Edgar Hoover’s FBI with the legal authority and jurisdiction to purge gay and lesbian federal employees from the federal employment rolls.”

“It is now time for the Department of Justice to remove the seal from this dark chapter of LGBT American history,” Frances said. “This is a history that has been sealed or destroyed by government agencies for decades, and it is more relevant than ever for judges, legislatures and the legal community—from North Carolina to Mississippi and beyond—to see the historical roots of the administration of animus against a powerless minority.”

“Whether wrapped in claims of ‘religious liberty’ or ‘bathroom bill’ privacy, an anti-LGBT backlash is underway across the country. Courts, the legal community, and voters must have access to the evidentiary history we seek,” Francis continued.