A federal appeals court ruled Tuesday the Justice Department must give Congress access to secret grand jury evidence from Mueller’s investigation into Russian interference in the 2016 presidential election.

The Justice Department must provide House Democrats access to secret grand jury evidence from former special counsel Robert Mueller’s investigation, a federal appeals court ruled Tuesday.

In a 2-1 ruling, the U.S. Court of Appeals for the D.C Circuit upheld a lower court’s order requiring the Justice Department to disclose this secret material to the House. The lone dissenter, Judge Neomi Rao, was appointed by President Trump.

The ruling can and likely will be appealed to the full court or the Supreme Court, but Tuesday’s decision represents a victory for House Democrats, who are investigating whether President Trump lied to Mueller or committed potential obstruction of justice during Mueller’s investigation into Russian interference in the 2016 presidential election.

Justice Department lawyers said the House Democrats’ lawsuit was a political maneuver and argued that exemptions allowing disclosure in certain cases do not apply to an impeachment proceeding. House lawmakers, meanwhile, said they needed access to the secret evidence to try and determine whether Trump lied in his written responses to questions from Mueller’s investigators.

The judges ultimately sided with House Democrats and upheld the prior decision from Chief U.S. District Judge Beryl A. Howell. Howell found that the House, as part of its impeachment investigation, was entitled to the grand jury materials because it was proceeding with a judicial process—impeachment—that exempts Congress from secrecy rules that usually allow grand jury materials to remain secret.