Electoral Strategies in Mixed Systems of Representation

The dispute over the conflicting merits of proportional representation (PR) and plurality (PL) electoral systems is mainly a debate over which element, representation or stability, should be emphasized. Advocates of PR do not accept policies as democratically valid if they are made on an inadequate representational base. On the other hand, advocates of PL argue that representation is meaningless if it is achieved at the expense of any possible agreement among the policy makers. These arguments appear repeatedly in the literature and with more practical impact, in constitutional assemblies. One of the outcomes of these arguments has been the development and implementation of mixed electoral systems that attempt to capture the strengths of both PR and PL systems. In this paper we analyze how parties form electoral coalitions in multiparty systems with mixed PR/PL electoral rules. We stress that mixed system of representation are created in the attempt to balance governance and representation by assigning a portion of the legislature’s seats on the basis of plurality and the remaining seats on proportional basis. This is operationalized through double-ballot-voting: a PL ballot for the allocation of the seats won by the candidates in single-member-college races and a PR ballot for the proportional allocation of the remaining seats among the competing parties. The aim of the paper is to formulate a general model to describe the electoral incentives that mixed electoral rules provide to political agents in multiparty systems. Italian 1994 and 1996 national elections are used as a case study to test the validity of our theory.