There is a comforting fiction circulating in Washington that the Senate parliamentarian holds a kind of veto over what Congress may and may not do. According to this fiction, when Elizabeth MacDonough offers advice that a provision violates the Byrd Rule, the matter is settled, the provision dies, and elected senators must simply accept the verdict of an unelected staff official appointed during the Obama administration. This is not how the Senate works. It has never been how the Senate works. And John Thune, of all people, knows it is not how the Senate works, because in May of 2025 he proved the opposite with his own hands. The clean way to state the principle is this. The parliamentarian advises, the chair rules, and the Senate decides. That ordering is not a clever workaround invented for the present moment. It is the basic architecture of Senate procedure. The Congressional Research