An adviser to U.S. District Judge Emmet Sullivan has argued that Sullivan both can and should deny the federal government’s motion to dismiss charges against President Trump’s former national security adviser Michael Flynn. “The facts surrounding the filing of the Government’s motion constitute clear evidence of gross prosecutorial abuse,” the adviser, ex-judge John Gleeson, argued in a court filing on Wednesday. “They reveal an unconvincing effort to disguise as legitimate a decision to dismiss that is based solely on the fact that Flynn is a political ally of President Trump.”

When federal prosecutors took the extremely unusual step last month of requesting that the court dismiss the case against Flynn—who had already pleaded guilty to lying to the FBI—Sullivan appointed Gleeson to argue against the government’s case. Gleeson said in his filing that Sullivan should proceed to sentencing Flynn. Despite pleading guilty, Flynn changed his legal strategy recently to claim that the FBI entrapped him, a claim backed up by Trump. Oral arguments for Flynn’s appellate case are set for Friday.