On the Absence of Centripetal Incentives in Double-Member Districts

Abstract

In its final months, the Pinochet regime engineered a number of institutional reforms with the intent of bolstering the right side of the spectrum and of promoting centripetal political competition once democratic procedures were reinitiated in 1989. One of the most important reforms created 60 double-member districts for elections to the lower house. Although some analysts have claimed that the new system does in fact promote centrist position taking, using game theory and spatial modeling, the authors demonstrate that the incentives of the Chilean electoral system encourage politicians to take noncentrist positions along a left-right spectrum. The combination of double-member districts with the d'Hondt seat allocation method and open-list voting creates a Rival Partners Game, creating perverse incentives for Chilean candidates. The authors' theoretical results help clarify the debate about the effects of post-authoritarian institutional reforms in Chile and should encourage empirical research on the same issues.

Origins of the Chilean Binominal Election System

“…Assuming that the extremes of the political spectrum represent minorities, the candidates who could attract the widest possible base of support would normally be centrists. 20 Marín's contention that the binominal system produces a dynamic of centripetal has since been called into question by several political scientists (Magar et al, 1998). They have made a formal argument based on spatial modeling and game theory that the binominal system does not encourage centripetal competition and, in fact, offers candidates "incentives to adopt positions away from the median voter" (Magar et al, 1998: 715).…”

PARTIES, COALITIONS, AND THE CHILEAN CONGRESS IN THE 1990s

“…The interviews suggest that discipline at the coalition level is a function of moral obligation rather than by sanctions imposed on maverick legislators. An alternative source of discipline is the electoral incentive under the M=2 system for candidates from the same coalition to stake similar ideological positions while distinguishing themselves from the candidates of the other main coalition, as implied by the formal models of Dow (1998) and Magar, Rosenblum, and Samuels (1998) A second implication, following from the cohesiveness of coalitions in the Chamber, is that the existence of non-elected senators means that much of the most important deliberation and negotiation within the legislature should take place between, rather than within, chambers. In the absence of non-elected senators, Chile's would be an example of congruous bicameralism, in which one would expect majorities in each chamber to generate similar decisions, because the electoral systems for the Chamber and Senate are identical (with the caveat that Senate districts are larger) (Lijphart 1984).…”

Ideological extremism and electoral design. Multimember versus single member districts

“…Cox (1997) examined the implications of his spatial models with case studies in nations having various forms of MMD, where he found evidence supporting the extremism hypothesis. Similarly, in two studies of Chilean MMDs, Dow (1998) and Magar et al (1998) also find support for the extremism hypothesis. In the American context, Schiller examined the U.S. Senate (a staggered MMD) and finds evidence that "a combination of electoral incentives and institutional forces .…”