The Balance between Small and Large: Effects of a Double-Majority System on Voting Power in the European Union

Abstract

In the beginning of 1995, the European Union (EU) has been enlarged by three countries: Austria, Finland, and Sweden. In view of the implications on the EU's institutional balance and the possible accession of more states in the future, different proposals are currently made to change the system of decision making to one that is more transparent and that more adequately represents member-states' population sizes. The issue will certainly be intensely debated in the framework of the 1996 Review Conference of the Maastricht Treaty. One of the current suggestions aims at establishing a double-majority voting system in the Council of the EU—formerly the Council of Ministers—requiring a majority of both member-states and their populations within that institution. Another one aims at introducing a bicameral system. This article analyzes what effects the resort to a double-majority voting system and the introduction of a bicameral structure would have in terms of the member-states' quantitative influence in the EU's decision-making process. Voting under the double-majority requirement is modeled by a simple game and relative voting power calculated by a (composite) Banzhaf power index.