Donald Trump’s unilateral effort to reshape election processes is an attempt to “short-circuit Congress’s deliberative process by executive order,” a federal judge in Washington, D.C. wrote Thursday afternoon.

In a 120-page opinion, U.S. District Judge Colleen Kollar-Kotelly blocked the Trump administration from requiring proof of citizenship to register to vote and ordering that election officials “assess” the citizenship of anyone who receives public assistance before allowing them to register. She also barred the Election Assistance Commission from withholding federal funding from states that did not comply with the order.

“Our Constitution entrusts Congress and the States—not the President—with the authority to regulate federal elections,” she wrote. “No statutory delegation of authority to the Executive Branch permits the President to short-circuit Congress’s deliberative process by executive order.”