The Quantitative Empirics of Redistricting Litigation: Knowledge, Threats to Knowledge, and the Need for Less Districting

Abstract

The experience of the past 50 years has taught us important lessons about the advancement in, but also the ultimate limits of, the quantitative empirics of redistricting. I provide a bird's eye view of the state of quantitative methods in redistricting, focusing particularly on the hardest problem in this area, inferences about racial bloc voting. I review some of the recent advances, particularly those that allow analysis of polities with more than two racial groups, and those that allow a combination of information from sampling techniques, such as exit polls, and so-called “ecological” data. But I also suggest that modern demographic and voting trends, along with a growing realization that there are some critical questions we will never be able to answer (at least not with quantitative information), provide reason for pessimism about how much useful evidence quantitative methods can ultimately produce. I suggest that the increasing limits of quantitative techniques, particularly with respect to voting patterns by race, provide an additional reason to explore the judicious use of alternative vote aggregation schemes, such as limited and cumulative voting.