Mixed-member electoral systems combine two distinct types of electoral rules
that embrace two distinct types of representation: local representation through elections
where voters cast a vote for individual candidates in local districts (the nominal tier), and
national representation through elections for parties in multiple-candidate list elections
(the list tier) (Shugart and Wattenberg 2001). The uniqueness of the mixing of
representation, coupled with the global spread of mixed-member systems in new and old
democracies, has spurred significant research among political science scholars. These
scholars have researched topics such as the choice of a mixed-system over other
alternatives
and mixed-member system effects on both the party system and voting
behavior.
In addition to these topics, some scholars have begun analyzing the potential
legislative behavior effects of mixed-member electoral systems.
The majority of these
studies test the “mandate divide” hypothesis, which predicts that the mixing of
representation and electoral incentives will lead to divergent legislative behaviors by
legislators with different electoral mandates.
While the existing studies of the legislative effects of mixed-member systems
provide us with an excellent foundation, they have been, in general, limited to questions
surrounding either party discipline or party switching. With the notable exception of
Stratmann and Baur (2002), little research has been done analyzing the effect of mixed-
member systems on legislative committees. This is surprising, given the intense debate
in the U.S. Congress literature on committees that is founded on the same basic question
that drives the research on mixed-member legislative behavior: what are the effects of
electoral rules? The Congressional debate over committees is centered on distributional
theories that argue that the U.S. single-member district electoral system drives the
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