Three Tests for Practical Evaluation of Partisan Gerrymandering
Three Tests for Practical Evaluation of Partisan Gerrymandering
复制标题
党派不公正划分的实际评估的三个测试
DOI：
10.2139/ssrn.2671607
复制
发表时间：
2015
影响因子：
4.9
通讯作者：
S. Wang
中科院分区：
文献类型：
--
作者：
S. Wang
自1986年美国最高法院对戴维斯诉班德默案（Davis v. Bandemer）的裁决以来，为争取全州选举优势而进行的党派不公正划分一直被认为是可予审理的。现行的最高法院标准，在Vieth v. Jubelirer和LULAC v.佩里案中达到顶峰，认为对不公正划分选区的检验应该同时证明意图和效果，而党派不公正划分选区可以通过其不对称性来识别：对于给定的普选分布，如果政党在普选中交换位置，席位数量将以不平等的方式变化。然而，不对称性标准只是一个宽泛的原则声明，最高法院尚未认定评估不对称性的分析方法是可行的。本文提出了三个统计检验来可靠地评估州一级选区方案中的不对称性：（a）基于全国选区特征的预期赢得的席位数的不代表性扭曲;（B）两党之间赢得选票差额的差异;以及（c）为负责重划选区的政党构建可靠的胜利，以平均和中间投票份额之间的差异来衡量，或者是在不同地区的选票分布异常均匀。第一个测试依赖于计算机模拟，以估计适当的代表性水平为一个给定的普选水平，并提供了一种方法来衡量一个gerrymander的影响。第二项和第三项测试是评估意图，依据的是既定的统计原则，可以使用手持计算器进行，而无需检查地图或重划选区程序。我将这些标准应用于各种选区划分方案，从1812年最初的“格里-曼德选区”开始，一直到现代的情况。在2010年后的国会选举中，少数几个州的党派不公正划分所产生的影响大于全国人口聚集的总影响。通过在最近的两个案例中应用这些标准，我表明，亚利桑那州的立法区（哈里斯诉亚利桑那州独立选区重划委员会）没有资格作为一个党派gerrymander，但马里兰州的国会选区（夏皮罗诉麦克马纳斯）。我建议，基于这些测试的意图和效果标准是足够强大的，以减轻需要证明占主导地位的党派意图。这里提供的三个统计标准增加了法官的工具包，以快速和严格地确定重划选区的影响。
Since the United States Supreme Court’s Davis v. Bandemer ruling in 1986, partisan gerrymandering for statewide electoral advantage has been held to be justiciable. The existing Supreme Court standard, culminating in Vieth v. Jubelirer and LULAC v. Perry, holds that a test for gerrymandering should demonstrate both intents and effects, and that partisan gerrymandering may be recognizable by its asymmetry: for a given distribution of popular votes, if the parties switch places in popular vote, the numbers of seats will change in an unequal fashion. However, the asymmetry standard is only a broad statement of principle, and no analytical method for assessing asymmetry has yet been held by the Supreme Court to be manageable. This Article proposes three statistical tests to reliably assess asymmetry in state-level districting schemes: (a) an unrepresentative distortion in the number of seats won based on expectations from nationwide district characteristics; (b) a discrepancy in winning vote margins between the two parties; and (c) the construction of reliable wins for the party in charge of redistricting, as measured by either the difference between mean and median vote share, or an unusually even distribution of votes across districts. The first test relies on computer simulation to estimate appropriate levels of representation for a given level of popular vote, and provides a way to measure the effects of a gerrymander. The second and third tests, which evaluate intent, rely on well-established statistical principles, and can be carried out using a hand calculator without examination of maps or redistricting procedures. I apply these standards to a variety of districting schemes, starting from the original “Gerry-manderˮ of 1812 up to modern cases. In post-2010 Congressional elections, partisan gerrymandering in a handful of states generated effects that are larger than the total nationwide effect of population clustering. By applying these standards in two recent cases, I show that Arizona legislative districts (Harris v. Arizona Independent Redistricting Commission) fail to qualify as a partisan gerrymander, but Maryland’s Congressional districts (Shapiro v. McManus) do. I propose that an intents-and-effects standard based on these tests is robust enough to mitigate the need to demonstrate predominant partisan intent. The three statistical standards offered here add to the judge’s toolkit for rapidly and rigorously identifying the effects of redistricting.