Legal Developments and Standards in Partisan Gerrymandering

Abstract

This chapter explores the legal history and recent court proceedings surrounding partisan gerrymandering, revealing courts to be less than ideal venues in which to sort out competing and possibly noncommensurate claims for fair representation. The chapter begins by framing Justice Kennedy’s search for a universal standard to evaluate partisan gerrymanders in his opinion in Vieth v. Jubelirer. The chapter then details the arguments and decisions in four cases decided in the past few years: Whitford v. Gill, League of Women Voters v. Pennsylvania, Benisek v. Lamone, and Rucho v. Common Cause. For each of the cases, it outlines the unique legal claims by the plaintiff and, where relevant, the arguments accepted and rejected by the court. It then applies a “stylized test” drawn from each case to the facts of the other cases, showing how the standards suggested in one may lead to divergent outcomes in another.

Asymmetries in Potential for Partisan Gerrymandering

“…That is, for every 1% increase in a party's vote, with should expect a 2% increase in the party's seats, and thus a party that wins 55% of the vote should win 60% of the seats. While this 2:1 seats:votes slope is derived by Stephanopolous and McGhee through the normative concept of "wasted votes", is has also been shown to match historical averages of U.S. congressional elections over many decades in such works as Tufte (1973) and Goedert (2014Goedert ( , 2022. Thus we use the efficiency gap baseline as a measure of the partisan deviation of a map from what we would expect from an historically average map.…”

“…Engstrom 2006;McDonald 2004;Stephanopolous and McGhee 2015), with most finding substantial partisan gains by both parties in most cases, though other works have cautioned that partisan effects may be sensitive to timing and national political conditions (see e.g. Gelman and King 1994;Seabrook 2017;Goedert 2022). And other authors quantify maximal gains or delineate optimal gerrymandering strategy under highly abstract theoretical models (e.g.…”