The Limits of Partisanship in Citizen Preferences on Redistricting

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Devin McCarthy recently presented a paper at the 2019 ESRA conference entitled, “The Limits of Partisanship in Citizen Preferences on Redistricting.” Here, he summarizes his analysis from that paper.

Redistricting has never been closer to the forefront of the public consciousness, but we still know little about how the American public thinks about the issue. This study aims to better understand how American citizens make one of the most basic redistricting tradeoffs: whether to prioritize a fair process or to maximize the number of seats won by their preferred political party.

I use two survey experiments to test whether partisan interest is the primary driver of public opinion on redistricting or whether citizens are constrained by beliefs in democratic principles and procedural fairness. Both surveys ask respondents to choose among several districting proposals, some of which are designed to appear as fair maps and some of which are designed to appear as gerrymandered.

The study tests two core hypotheses. First, I expected that respondents who are presented with a redistricting scenario in an abstract context with fictional parties will be more likely to choose independent redistricting than those who are choosing in the context of a real state in which their own party has majority control. Second, I expected that showing partisans examples of the opposing party engaging in egregious gerrymandering would make them more likely to want to gerrymander themselves, so as to avoid “unilateral disarmament.”

In the first experiment, each respondent saw a set of four maps of either Maryland (for Democrats) or North Carolina (for Republicans) and was asked to pick one. One map represents the actual gerrymandered map implemented in 2012, one map represents what a nonpartisan commission might draw, one map represents an even more extreme gerrymander labeled as drawn by the respondent’s party, and one map represents an extreme gerrymander labeled as drawn by the opposing party.

Respondents were also randomly assigned to one of four experimental groups. Those in the control group were shown a map of what is described as a fictional state called Americana (but is in fact Maryland/North Carolina with parts of the state cut off). Party labels were fictional as well, with the “American Party” standing in for the Republican Party and the “National Party” standing in for the Democratic Party. A “Partisan” group saw maps with Democratic/Republican partisan labels and the real geography of MD/NC. A “Distrust” group was first shown an example of the opposite party gerrymandering to prime distrust of the other party, then asked to choose among the same maps as the Partisan group. Finally, a “Trust” group was shown the same material as the Distrust group, but with the opposite party also proposing an interstate nonpartisan redistricting compact.

Partisans of both parties were more likely to choose a gerrymandered map when party labels were present compared to a hypothetical scenario with fictional parties. However, the difference was not large, and clear majorities of respondents chose the fair map across all experimental conditions and parties. Furthermore, the respondents who were most affected by the addition of party labels were the small minority of Americans for whom their political party is an important part of their social identity. The treatment groups who were shown evidence of the other party engaging in gerrymandering were no more likely to prefer gerrymandering themselves (though neither were the groups told that the other party was willing to adopt independent redistricting more likely to choose the nonpartisan option).

The second experiment is a pared down version of the first, replacing visual maps with verbal descriptions and giving respondents a binary choice between a map that is gerrymandered such that their party wins all the seats in a state (in this case, Indiana for Republicans and Maryland for Democrats) and a map drawn by a nonpartisan commission that produces an outcome proportional to the partisan split of the state. In this scenario an even more decisive majority of respondents preferred the nonpartisan option over the gerrymander. The nonpartisan commission was selected by 74% of Democratic and 78% of Republican respondents. The results of this experiment offered mixed support for my second hypothesis. Democratic respondents told about Republican gerrymandering in Indiana were significantly less likely to support a nonpartisan commission in Maryland, but Republicans told the same thing about Democratic gerrymandering were no less likely to choose a nonpartisan commission in Indiana.

In sum, this study demonstrates that many Americans are able to make coherent decisions about redistricting and will not blindly follow the party line on the question of how to draw districts. To be sure, partisanship does matter for public opinion on redistricting. But the dominant story that emerges from these surveys is that the American public cares about democratic values. A clear majority of survey respondents across both surveys chose a fair, nonpartisan map over a map gerrymandered in favor of their party. Most respondents strongly endorsed values related to support for multi-party democracy, and these values were strongly associated with choosing a fair map. Those who did choose gerrymanders tended to come from the small set of people who view their party as an important social identity. Even when shown treatments explicitly designed to engender distrust of the opposing political party and the redistricting process, clear majorities of respondents continued to select the nonpartisan option.

These findings are instructive for policymakers heading into the 2020 redistricting cycle. While attempts to engage in partisan gerrymandering may be met with tolerance or even approval by committed partisans, most citizens, including those who share a party with the gerrymanderers, will not approve. If awareness of redistricting continues to rise in the mass public, there could be greater consequences for partisan gerrymandering in the next round of redistricting than there were in the last, both for the legitimacy of American legislatures and the electoral fortunes of parties engaging in gerrymandering.