A federal appeals court appeared skeptical Friday of the Trump administration’s bid to build the proposed White House ballroom, but it also sharply questioned whether a preservationist group can even sue to stop the project.

A three-judge panel on the U.S. Court of Appeals for the D.C. Circuit heard arguments from both the Department of Justice and lawyers for the National Trust for Historic Preservation on whether to reverse a lower federal judge’s order halting construction of the East Wing renovation project. The DOJ has largely argued that halting construction would jeopardize the security and safety of the president and the White House complex, but during Friday’s hearing, the judges focused their questioning on whether the preservationist group has proven enough of an injury to sue over the construction project.