Raising the Threshold, Fighting Fragmentation? Mechanical and Psychological Effects of the Legal Electoral Threshold in Belgium

Abstract

Many proportional representation systems are characterised by a legal electoral threshold. Such a threshold reserves the allocation of seats for those parties that reach a minimum share of the votes. In order to fight fragmentation, a 5 per cent threshold has been introduced for both federal and regional elections in Belgium. This article seeks to explore the mechanical and psychological effects of this legal threshold after five elections. It is shown that the threshold has had limited mechanical and psychological effects on voters but some psychological effects on party elites. Moreover, while in the short term the average number of lists dropped and several pre-electoral coalitions formed, in the longer term the legal threshold has not prevented further fragmentation.

Acknowledgements

We acknowledge financial support from the Fonds de la Recherche Scientifique – FNRS, Belgium. We would also like to thank Frédéric Bouhon, Marc Hooghe and this journal’s reviewers for useful comments at earlier stages of this article. The data used in this article come from official election results, ISPO/PIOP 2003 General Election Study – Belgium (codebook and questionnaire, KU Leuven/UC Louvain), PartiRep Election Study – Regional Elections 2009 (Brussels: PARTIREP) and our own calculations.

Notes

1. Where S is the total seats share obtained by the parties (S = S1 + S2 + ... + Sn) and where V is the total votes share obtained by the parties (V = V1 + V2 + ... + Vn).

(a) represents the result without the legal threshold and (b) with the legal threshold.

2. Where S is the total seats share obtained by the parties (S = S1 + S2 + ... + Sn).

3. According to Laakso and Taagepera’s formula (1979).