Contextual Determinants of Electoral System Choice - Ã bo Akademi

2.2.1 Plurality Systems2.2.1.1 Single-Member PluralityIn a plurality system, the candidate or party with the largest number of votes wins,irrespective of the proportion of the total vote. In contrast to majority systems, it ispossible to win an election without winning a majority of the votes. The mostcommon plurality formula is the single-member plurality formula, also called,among other things, ‘simple majority’, ‘relative majority’ and ‘first past the post’.In the present study, the term single-member plurality (SMP) is used, because itcomprises the main features of the formula, and distinguishes it from otherplurality formulas. Only single-member constituencies are used, voters are givenone vote each, and the candidate or party with a plurality of the total vote iselected. In a historical sense, SMP is associated with the United Kingdom. Thesingle-member constituency was introduced into Britain in 1707, but it did notbecome the general basis of representation until 1885 (Bogdanor 1983: 3; Lakemanand Lambert 1954: 25). The plurality system had earlier operated mainly in twomemberdistricts. Vernon Bogdanor (1983: 3) points out that before SMP became anorm in Britain, it was already the predominant basis of representation in theUnited States, Canada, Australia and New Zealand.The great advantage of this formula is that it produces firm government, or, in anycase, that it is much more likely to do so than PR systems (see e.g. Blais andMassicotte 1996: 73-75; Lijphart and Grofman 1984b: 5-7). By discriminatingagainst small parties, it often provides a clear-cut choice for voters between twomain parties, which, in turn, gives rise to single party governments and a coherentparliamentary opposition. It also restrains extremist parties from receivingparliamentary representation. Moreover, SMP is defended on grounds of simplicityand geographic accountability, i.e. the link between constituents and theirrepresentatives created by small constituencies, as well as the choice betweencandidates rather than between parties. The basic demerit of SMP is thedisproportional seat allocation, which leads to under-representation of smallparties, minorities and women. Because of the disproportionality, SMP electionsalso produce a large number of ‘wasted’ votes; i.e. votes cast for unsuccessfulparties and/or candidates. Finally, gerrymandering and malapportionment often20