Chris Kenny (APRW)

This Week's Speaker

Chris Kenny, "Evaluating the Effectiveness of Congressional Redistricting Commissions"

Abstract

Every decade, districts in the United States are redrawn following the US census. Map drawers have the ability to manipulate this process to create partisan gains in a process known as gerrymandering. When gerrymandering occurs, it can be seen as a threat to democracy, as it makes elections less responsive to voter interests. Indeed, recent research confirms that many states’ enacted redistricting plans show evidence of partisan manipulation. 

To remedy concerns about gerrymandering, many actors have pushed for the adoption of redistricting commissions. Commissions generally move redistricting from the hands of state legislators into the control of a group of citizens, though the specific design differs by state (Cain 2012). The idea behind this is simple: removing politicians from the redistricting process makes districting less susceptible to direct partisan interference. Over the past two decades, about a dozen states have adopted redistricting commissions for drawing congressional and legislative districts.

Existing research has demonstrated mixed results on the efficacy of redistricting commissions, with primarily positive or null findings. However, two primary issues persist across this research. First, most evaluations of redistricting commissions do not account for underlying political geography. Each state’s unique geography directly impacts the space of what partisan outcomes are most typical. Notable exceptions to this critique include (Warshaw, McGhee, and Migurski 2022) and (Best et al. 2021), though each looks at only a subset of states over recent decades. Second, when states select into adopting redistricting commissions, they typically adopt more specific standards for what map drawers should consider. This means that states with commissions typically have clear rules for redistricting, whereas states without commissions often have only very basic rules or no rules at all. For example, Illinois has no formal rules for redistricting and must only comply with federal law. In contrast, Michigan’s constitution lays out eight detailed requirements that must be considered and their relative priorities.

To rectify these issues, I collected and classified each state’s legislation, constitutional provisions, and formal resolutions regarding redistricting. I then combine this data with sampled redistricting plans to compute relative measures of partisan fairness. This allows me to make more proper comparisons between commission-drawn and legislature-drawn plans.

I focus on congressional redistricting in the 2020 cycle (with 2010 in progress), where the ALARM Project has sampled large sets of counterfactual redistricting plans that follow each state’s individual legal constraints (McCartan et al. 2022). For each state, I produce estimates of seat shares, competitiveness, common metrics of partisan bias (Katz, King, and Rosenblatt 2020), incumbent protection, and differential partisan harm (McCartan and Kenny 2022). Each estimate is normalized using the corresponding estimates from the simulated plans, allowing for comparability between states.

Preliminary results indicate that there is a difference in fairness outcomes exists between commissions and legislatures, consistent with existing literature. However, when comparing commissions and legislatures after accounting for compliance with relevant rules, there is no difference present. This underscores the importance of how state statutes can limit the ability to gerrymander directly. Further, these preliminary results cautiously suggest that redistricting reform efforts should allocate more energy to reforming rules, rather than focusing only on process-oriented reform.

The American Politics Research Workshop (Gov 3004) meets all academic year, Tuesdays, 12:00 - 2:00 PM, in CGIS K354. This workshop presents an opportunity for graduate students and Harvard faculty to present and receive feedback on their current research. The workshop highlights key theoretical and empirical findings from Harvard affiliates on topics related to American politics.

All interested Harvard affiliates are invited to attend.