My research interests cover the intersection between politics, geography, and population change, with special attention toward urban politics and the environment. Methodologically, I couple original data sources with causally identified research designs to examine how political processes and behaviors vary across physical space.   


Households with solar installations are ideologically diverse and more politically active than their neighbors (with Matto Mildenberger and Peter Howe). 2019. Nature Energy, 4, 1033–1039. 

Climate risk mitigation requires rapid decarbonization of energy infrastructure, a task that will need political support from mass publics. Here, we use a combination of satellite imagery and voter file data to examine the political identities of U.S. households with residential solar installations. We find that solar households are slightly more likely to be Democratic; however, this imbalance stems primarily from between-neighborhood differences in partisan composition rather than within-neighborhood differences in the rate of partisan solar uptake. Crucially, we still find that many solar households are Republican. We also find that solar households are substantially more likely to be politically active than their neighbors, and that these differences in political participation cannot be fully explained by demographic and socioeconomic factors. Our results demonstrate that individuals across the ideological spectrum are participating in the U.S. energy transition, despite extreme ideological polarization around climate change. 

Drivers of support: The case of species reintroductions with an ill-informed public (with Elizabeth Hiroyasu and Sarah Anderson). 2019. Human Dimensions of Wildlife, 24:5, 401-417.

Successful rewilding of large carnivores depends on public acceptance, but the public frequently has little awareness about wildlife and specific reintroduction proposals. This article evaluated the determinants of public support for grizzly bear reintroduction in California to understand how value orientations, political ideology, and demographics predict attitudes when the public has little species-specific knowledge. We surveyed 980 Californians, showing that value orientations, awareness, and perceptions of costs and benefits shaped attitudes toward grizzly reintroduction, even when only one-quarter of the respondents knew that grizzly bears were extirpated from California. Almost two-thirds of respondents were supportive of reintroduction, rationalizing their support with assessments of societal and ecological costs and benefits. Lack of public awareness, perceptions of personal threats, and willingness to rationalize stated preferences provide cautionary notes to managers. Our results suggest that managers should offer early articulation of costs, benefits, and threats before reintroductions become politicized and opposition becomes entrenched.

Working Papers

Achieving parity: Identifying the impact of district elections on minority representation in local government. Under Review. Draft

Though common knowledge suggests that district-based electoral systems increase minority representation, empirical evidence is surprisingly mixed. This letter uses an original dataset of California municipal governments to adjudicate between existing research by providing casually identified estimates of their impact. Examining elections between 2008 and 2016, I show that district elections increased minority representation by roughly 20 percentage points. I also show that they increased the demographic similarity between city councils and the cities they represent by roughly 15 percentage points. These results are robust to various identification strategies and model specifications. The findings speak to the impact of electoral systems on representation, and suggest that district elections can be a viable strategy to increase the voice of historically underrepresented groups. 

Redlining revisited: The Home Owner’s Loan Corporation and the political geography of Los Angeles.

In the 1930s, the Home Owner’s Loan Corporation (HOLC), a New Deal Program initiated by Franklin Delano Roosevelt, created risk assessment maps in over 200 cities across America to stabilize housing markets. These maps intended to guide mortgage lenders by identifying the loan default risk associated with lending to households in different neighborhoods. While economists, sociologists, and demographers have explored the effect that these maps had on local housing markets, racially-motivated lending practices, and “redlining”, little is known about their impact on the political system. Using an original panel dataset that combines geocoded historical voting precinct maps, digitized historical voting precinct returns, digitized HOLC risk assessment maps, digitized HOLC area descriptions, and address-level 1930 Census data, this project identifies the causal effect that redlining had on the political geography of Los Angeles County. To do so, this paper uses geographic discontinuities and matched sample comparisons at fine spatial scales (i.e., street-level) to identify causal effects between areas that received HOLC assessments to those that did not by comparing units that, aside from treatment status, are otherwise identical. This paper contributes to the existing literature by expanding our knowledge of the yet-understood impact that this program had on political life in the US.

Demographic and political change: The Great Migration's impact on the ideological and policy references of elected officials. 

The first and second Great Migrations were two of the largest demographic events in American history, and they fundamentally changed the social, cultural, and economic makeup of the Northeast, Midwest, and West. However, existing data limitations and threats to inference have made identifying their impact on the political system challenging. Using a novel dataset, identification strategy, and historical passenger railroad routes as an instrumental variable, this project identifies the causal impact that the Great Migrations had on the ideological and policy preferences of Congress members in the Midwest and Northeast. Results show that this demographic event affected the preferences of elected officials in some, but not all, areas that received Black migrants, that Black migration was associated with a shift to more liberal ideological and policy stances, and that Congressional districts with major North-South rail lines received the largest number of Black migrants. This paper not only contributes to our understanding of the dynamics of constituent - Congress member relations, but also to the way large demographic events affect the political system.

Prevalence and predictors of wind energy protests in the United States (with Leah Stokes).

Addressing climate change requires societies to transition towards low-carbon sources, including renewable energy. By far the biggest growth area is wind energy. Unfortunately, this technology has proven politically controversial, with social movements arising to protest wind energy projects across North America. While some research has examined specific cases of public resistance toward specific wind energy projects, there is no systematic study of wind projects on a larger scale, to identify the prevalence of protests and examine predictors of local resistance toward wind energy projects. This project uses a novel dataset of wind energy projects in the United States to examine drivers of protest toward renewable wind energy projects. The results show that project-specific features such as total energy produced and wind speed affect the likelihood of protest. Additionally, geographic and census-tract level demographic characteristics predict protests, as well.