Royal Prerogative powers allow Prime Ministers to take the country to war without any formal requirement for the consent of Parliament. Votes for military involvement in Iraq and against it in Syria have helped established a convention for consultation with the House of Commons over military action, but the ultimate legal authority still rests with the executive. Graham Allen MP argues that powers vested in the monarch but exercised by Ministers without a legal need for Parliamentary approval are an anachronism and that: ÒOnly by introducing a written constitution will it be possible fully to establish the principle that the executive derives all its powers from the people, and that it is accountable to them and their representatives for the way it uses themÓ.