A Discernable and Manageable Standard for Partisan Gerrymandering

Abstract

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Quantifying Gerrymandering Using the Vote Distribution

“…The matter of determining a standard for what qualifies as an unconstitutional partisan gerrymander is beyond the scope of this article. (See [MS15] for a comprehensive treatment utilizing the efficiency gap, [MSK15] for the seats-votes curve and [MB15,Wan16] for the mean-median difference.) In addition to the nontrivial task of addressing guidance from the courts, two significant issues that must be addressed are the reality that any measure of asymmetry in vote distributions will vary from election to election (see Fig.…”

Can Gerrymanders Be Detected? An Examination of Wisconsin’s State Assembly

“…They dismiss the concept of proportional representation as unrealistic in single-member districts where the winning party frequently receives a “winner’s bonus” in seats beyond their share of the votes, and argue the EG’s approach is normatively and legally superior. Several scholars object that this winner’s bonus is arbitrary and questionable on any yet to be articulated ethical grounds (McGann, Smith, Latner, & Keena, 2015). It is also the empirical by-product of the specific way in which votes are designated as wasted (see Note 5).…”

Theoretical Foundations and Empirical Evaluations of Partisan Fairness in District-Based Democracies

“…The assumed fair seats–votes curve in equation 22 meets the partisan symmetry standard in Definition 1 because S ( V ) = 2 V − 0.5 = 1 − [2(1 − V ) − 0.5], but it is a special case because of the additional constraints of a slope of ρ ( V ) = 2 for V ∈ [0.25, 0.75] and ρ ( V ) = 0 for V ∉ [0.25, 0.75] (the red line in the left panel of the figure in Online Appendix G); note that all four symmetric electoral systems in Figure 1 would be judged unfair according to this standard. Equation 22 is an unpopular normative standard (e.g., Chambers, Miller, and Sobel 2017, 16; McGann et al 2015, fn. 1), but it is coherent and so meets Assumption 1.…”