For over 40 years now, the debate on the hierarchical opinion structure within political parties has been colored by May’s laws of General and Special curvilinear disparity. Their essence is that, compared to non-leaders and top leaders, the mid-level of sub-leaders of parties consists of radicals as regards their ideological, substantive positions. Persistent as this vision is, however, there have been few comprehensive empirical tests. In this paper such a test is employed for Dutch parties, consisting of: a) a comparison of average positions on issues and in terms of left and right of voters, members and MPs; b) a comparison of the full opinion distributions on particular political issues for these groups; and c) an exploration of perceptions among top leaders and sub-leaders of the opinion structure within their party. We conclude that there is not enough support to uphold May’s laws any longer. His laws should be dismissed, but May’s legacy should consist of a more open study of the opinion structures of parties, which are still crucial actors in Western representative democracies.