A preliminary version was presented to a seminar In the Centre for the Study of Globalization and Rationalization at Warwick university:l would like to thank all participants for their moments. Title: Designing the Voting System for the Council of the European Union Author: Dennis Leech Affiliation: Department of Economics and CIGARS University of Warwick and Voting Power and Procedures Programmer, SPANS, London School of Economics. Abstract: This paper examines the system of Qualified Majority Voting, used by the Council of the European union, from the perspective of enlargement of the Union.

It uses an approach based on power indices due to Penrose, Bonanza and Coleman to make two analyses: (1) the question of the voting power of member countries from he point of view of fairness, and (2) the question of how the threshold number of votes required for KM should be determined. It studies two scenarios for change comprising 1 5 member countries, and (2) full enlargement to 27 members by the accession of all the present twelve candidates. The proposal is made that fair weights be determined algorithmically as a technical or routine matter as the membership changes.The analysis of how the threshold affects power shows the trade-offs that countries face between their blocking power and the power of the Council to act.

The main findings are: (1) that the weights laid down in the Nice Treaty are close to being fair, the only significant discrepancies being the under-representation of Germany and Romania, and the over-representation of Spain and Poland; (2) the threshold required for a decision is set too high for the Council to be an effective decision making body.Keywords: European Union; Nice Treaty; Qualified Majority Voting; Weighted Voting; Power Indices. 1 . INTRODUCTION The prospect of enlargement of the European Union by the accession of new member countries from Eastern Europe has posed fundamental questions about how its institutions of governance should change in response.

The Intergovernmental Conference held in Nice in December 2000 was held to address these issues and produce an agreement on the basic structures of decision making as a framework for enlargement.However the Nice Treaty has been criticized and should be regarded as only a limited success. The main focus of the conference was on the extension of the range of decisions taken by Qualified Majority Voting in the Council and on the technicalities of how this system would work from 2005 onwards. There was considerable discussion of how the weighted votes should be allocated to each member country and what the decision rule should be in terms of the threshold. The treaty made provision for new weights for the existing fifteen members and for twelve candidates.It also provided for changes to the decision rule in terms of the size of the majority required for a proposal to pass.

These changes have been analyses rigorously in terms of a priori voting power by Blumenthal and Makeover (2001 b) who concluded that, while the allocation of voting weights is relatively fair in the sense that the system gives electors in different countries ugly similar voting power, the threshold agreed on is set too high for the Council to be an effective democratic decision-making body.The present paper builds on that study, partly duplicating it, but also extending it. 1 1 investigate the properties of the voting systems laid down in the treaty to apply both before and after enlargement, duplicating the analysis of Blumenthal and Makeover (2001 b). I also consider the normative question of what the voting weights should be in order that the system is fair. I apply an algorithm for choosing the weights so as to achieve a given distribution of voting power among the members.

This is proposed as a general procedure that could be applied in a more or less routine manner each time the membership changes: every time a new member country Joins its voting weight can be calculated, and those of all existing members recalculated, by this algorithm in to determine the voting weights once and for all so that there would be no need to hold an Intergovernmental Conference every time new members Joined. The general procedure proposed is an alternative that would have the advantage of giving fair weights in all cases. I also investigate how the choice of decision rule affects voting rower given the Nice weights.I address the following specific questions in terms of a priori voting power. Separate analyses are reported for the Union comprising the existing 1 5 and after enlargement to 27.

Other studies of voting power in the EX. Council of Ministers include Hoses (1993, 1995, 1996, 1998), Widgeon (1994), Blumenthal and Makeover (1998, 2000), Laurelled and Widgeon (1998), Inurn and Mistaken (1999), Suttee (2000). A recent contribution on the Nice Treaty is Baldwin et al. (2001). 2 What is the distribution of voting power among the member countries given by the voting system and weights in the Nice Treaty?How should the weights be chosen if the aim is to ensure that all citizens of the EX.

have equal voting power? What is the effect of the threshold required for a decision by weighted majority voting on the power of the Council to act and also the powers of the individual members? The paper is organized as follows. Section 2 describes the system of Qualified Majority Voting, and the Nice Treaty is described in Section 3. Section 4 outlines the measurement of power under weighted voting, using the power indices due to Penrose, Bonanza and Coleman.The idea of fair weighting and reweighing is defined ND the algorithmic approach described in Section 5. Section 6 presents the analysis of the distribution of voting power and the fair weights under the Nice Treaty.