Law and virtue in a post-sovereign “Commonwealth:” Neil MacCormick and the political theory of constitutional pluralism

This paper reconstructs the political thought of the Scottish legal philosopher, and eventually MEP, Sir Neil MacCormick (1941–2009), the founder of “constitutional pluralism,” one of the most influential legal theories of the European union today. It argues that his legal theory is underpinned by a coherent and original political theory of post-sovereignty. But, contrary to many current interpretations, this article argues that normatively, constitutional pluralism is not a purely liberal theory. Neither is it inherently illiberal, as has been contended. Instead, this article spells out the hybrid institutional design imagined by N. MacCormick and inspired by the thought of D. Hume, as well as the lineaments of an ethical theory of post-sovereignty he developed. So doing, while I will argue that it ultimately leads to a kind of republican cosmopolitanism, the political theory of constitutional pluralism is shown to open up an important, if not fully developed, avenue to escape some shortcoming commonly associated with post-sovereignty.