electoral systems in general. The major insight remains that electoral systems are
not merely neutral systems for totting up votes and producing an outcome but
instead systematically privilege some parties over others: speciWcally, single mem-
ber simple plurality (SMSP) pushes party systems towards having two big parties,
more proportional electoral systems produce greater numbers of smaller parties.
There are a series of amendments, elaborations, and caveats made in relation to
that statement. Some proportional systems, for example, are more proportional
than others (Gallagher 1991 ). In addition there are a number of empirical studies on
the failure of Duverger (‘‘non-Duvergerian equilibria’’). Duverger’s Law may work
well enough within particular districts to produce two parties but that is not
necessarily the same as working nationwide to produce the same two parties. In
varying degrees Canada, India, and the UK do not conform neatly to the model
and explanations for this have been advanced that relate to social diversity and
federalism (see Chhibber and Kollman 2004 ; Riker 1982 ). But the basic argument of
Duverger remains. Cox ( 1997 ) provides the seminal discussion of a precise
statement of Duverger’s Law and the number of expected parties, anchoring his
interpretation in the kinds of coordination problems elections bring to the fore:
parties have to coordinate on which candidate(s) to put forward while voters have
to coordinate on which candidate(s) to vote for.
One reading of Duverger is that it remains a fairly simple statement about the
number of parties in a political system and the role of the electoral system in
shaping that number. But it is possible to give Duverger a broader reading by
noting the wider consequences of the number and ideological range of parties for
several features of politics. Some of those consequences concern governability or,
more accurately, the ungovernability that may be associated with multipartyism
while others relate to underlying normative ideas of representation and
accountability.
The examples of Weimar Germany, the French Fourth Republic, (most of)
postwar Italy, and Israel are often held to have pathologies of ungovernability
and the consequent encouragement of extremism that stem directly from multi-
partyism. In that sense, the tendency of electoral systems to reduce the number of
parties helps simplify coalition building which in turn helps put in place govern-
ments that last longer (see Laver and SchoWeld 1998 ). There are, it can be argued,
further payoVs in accountability for reducing the number of choices at election
time. The multiparty governments that tend to result from proportional systems
do not make for the easiest system of accountability since voters may be confused
over which governmental party to reward or blame. Coalitions may also be formed
in a way that can thwart voter attempts at reward and punishment if parties which
lose votes end up gaining a place in government (Anderson 1995 ; Powell 2000 ).
Accountability, then, is tied to the number of parties in government which is in
turn tied back to the number of parties successful at election time and, in its turn,
tied back to the operation of Duverger’s Law.
580 shaun bowler