Abstract The article criticizes the trend of reformulating the traditional just-war criterion of Proper Authority, which was designed to de-legitimize force by non-state actors, into a requirement that decisions to resort to force be multilateral. The article illustrates several shortcomings of the judgment processes of the UN Security Council and General Assembly, the World Court, and states? populations, and argues among other things that reformulating Proper Authority would render other criteria meaningless, especially Just Cause. Finally, the article rebuts the strongest (...) objection to a system in which states judge their own causes for war: the problem of invincible ignorance. (shrink)