Unaggrandizing the Partisan Gerrymander

Abstract

Abstract

Observers suggest the effects of redistricting with excessive partisan bias or gerrymandering are particularly distinct and durable today. In this telling, partisan polarization, sophisticated technology, and detailed information of voter behavior permit those who draw state legislative and congressional plans to secure favorable electoral outcomes for their party throughout the decade the plan is in effect. We provide an empirical test of this basic claim by comparing three plan “pairs”—essentially juxtaposing plans accused of exhibiting excessive partisan bias by academics, journalists, or the courts with equivalents that are not. Using traditional indicators of partisan bias in redistricting, we find evidence that gerrymandered plans differ less than implied by characterizations from the non-gerrymandered plans with which they are paired and that any advantage given to a party at plan conception tends to decline over the course of a decade as partisan bias in the gerrymandered maps declines and differences in plan pairs alleviate. We conclude with thoughts regarding the implications of our results for political scientists, potential litigants, and jurists.