Preston R. Johnston

PhD Candidate
MIT Political Science
Subfields: Political Economy and
Quantitative Methods

Photo credit to the Minda de Gunzburg Center for European Studies at Harvard University

I am a PhD candidate in the MIT Department of Political Science. My main research agenda examines the political consequences of rising climate risk, with a focus on how climate costs are spread across space and social groups. My projects often combine spatial climate data with causal inference tools to study how climate risk affects policymaking, political behavior, and interest group politics. My research aims to provide insights that help make climate adaptation effective, equitable, and politically durable.

My dissertation examines one of the most important impacts of climate risk in wealthy countries: disrupted property insurance markets. The project’s primary case is the United States, with comparisons to Australia and the UK.

I am also more broadly interested in the American Political Economy, especially money in politics.

I am a graduate student affiliate of the Minda de Gunzberg Center for European Studies at Harvard. Together with Clemente T. Sanchez, I also run the Comparative Politics and Political Economy (COPE) graduate student seminar at MIT.

Before graduate school, I received an undergraduate degree in Politics with a certificate in Statistics and Machine Learning from Princeton University. You can find my CV here.

Working papers

* indicates dissertation paper

Resisting Segmentation: Climate risk and the politics of insurance*

Abstract

Rising climate risk in the United States has destabilized property insurance markets, prompting policymakers to consider insurance reforms that redistribute the costs of climate change. I identify two opposing types of reform that move markets either towards greater segmentation (i.e., individualized, risk-reflective pricing) or more risk pooling. I present survey evidence that citizens facing higher climate risk show greater support for government intervention in insurance markets and pooling-based notions of fairness. I then use an LLM-based strategy to classify a comprehensive dataset of insurance-related bills introduced in state legislatures since 2016. In cross-sectional and difference-in-differences designs, I find that legislators representing high-risk districts are more likely to sponsor pro-pooling legislation. However, states where wealthy homeowners stand to benefit have been more likely to enact pooling reforms. This can result in what I call ‘regressive socialization,’ complicating the distributive implications of risk pooling policies.

Draft

Ethnicity and Climate Attitudes in Africa (with Devin Caughey and Evan Lieberman). Under review.

Abstract

Africa is the world region most vulnerable to climate change, but climate opinion on the continent varies widely. Building on the well-established importance of ethnicity for structuring politics in many African countries, we provide the first systematic examination of ethnic dissensus on this issue. Using Afrobarometer data from 29 countries, we first show that ethnic differences are statistically significant in nearly every country. We then show that while ethnic dissensus is often of modest magnitude and importance, in some countries ethnicity explains as much as 30% of the variation in survey responses. Contrary to theories emphasizing ethnic or regional inequality, these factors are not correlated with the severity of ethnic dissensus in a country. Rather, the best predictor of ethnic dissensus over climate change is the degree of ethnic segregation. These findings provide the first descriptive overview of ethnic cleavages on this emerging issue and point toward spatial concentration as a key driver of inter-group differences.

Draft

Voters Uncovered: Home insurance availability, electoral accountability, and climate adaptation*

Abstract

Do voters punish incumbents for the financial effects of climate change? If so, do policies that protect citizens from these effects produce electoral rewards? I study these questions in the context of the growing home insurance crisis in the United States. In recent years, home insurance premiums have risen significantly faster than inflation and the non-renewal rate, a measure of coverage unavailability, has more than doubled. Drawing on county-level panel data, I examine whether declines in home insurance availability caused anti-incumbent voting in gubernatorial and insurance commissioner elections in the period 2017-2024. I find that declining coverage availability results in an electoral penalty for Democratic governors, with more ambiguous effects on insurance commissioner elections. Given the potential political costs to coverage declines, I then analyze whether voters reward incumbents for policies designed to reduce non-renewals. I study a recent California policy that places one-year moratoria on non-renewals following wildfires. I find that moratoria that expire prior to the 2022 election reduce incumbent voteshare. This finding is explained by private insurers immediately increasing premiums following moratorium issuance and accelerating non-renewals following moratorium expiry. The results highlight the dilemmas facing governments dependent on private intermediaries to protect constituents from worsening climate risk.

Work in progress

Swimming in the Flood? Ideology and individual-level climate adaptation (with Clemente T. Sanchez)

Abstract

How do people adapt to climate change? Although individuals have incentives to reduce their exposure to climate risks, research has shown that risk perceptions and tolerance are socially constructed. We propose that political attitudes may affect the adaptive actions individuals take in response to climate risk. Studying the case of Brazil, a country that faces severe climate impacts, we combine experimental and observational data to examine whether ideology explains variation in adaptation behaviors and whether it moderates responses to risk exposure. First, we field a pilot survey experiment on participants sampled from flood-exposed municipalities, in which we administer an informational treatment revealing respondents’ local flood risk level. We measure how exposure to risk information alters stated and revealed adaptation behaviors, as well as support for adaptation-relevant public policies. Second, we leverage a large, government-administered survey of Brazilian rural households. Using this data, we develop a novel typology of self-reported behavioral responses to climate change. We then examine whether respondents in areas with more right-wing electoral preferences self-report different adaptation behaviors and whether they exhibit lower elasticities of such behaviors to climate risks such as droughts, floods, and landslides. We present pilot findings and discuss design considerations for a larger, pre-registered follow-up survey.

Post-pilot survey draft

The Role of Organized Business in Democratic Backsliding in the United States (with Alex Hertel-Fernandez and Kathleen Thelen)

Abstract

What role does organized business play in democratic backsliding? We study this question in the context of the United States over the last four presidential administrations. Although certain firms have reaped material returns from President Donald Trump’s transactional approach to governance, many other business interests have much to lose from both individual Trump policy decisions as well as the broader decline in rules-based governance. We might expect disadvantaged firms to delegate political resistance to business associations that can overcome collective action problems and provide political cover. Public speech from these associations might serve a coordinating role for firms who oppose the Trump agenda. We assemble a dataset of over 40,000 scraped press releases from 32 of the largest US business associations spanning over a decade and covering nearly every sector of the US economy. We use an LLM-based strategy to classify each press release’s stance towards the current presidential administration and whether it relates to democratic institutions. We identify three main patterns. First, differing with recent accounts that point to a realignment of business to the Democratic Party, we document a persistent Republican preference among the largest business associations, which has if anything strengthened during the second Trump Administration. Second, associations representing firms in more highly regulated sectors are more likely to praise both Trump administrations. Third, speech by associations explicitly mentioning democracy is vanishingly rare, constituting 0.2% of our total corpus and concentrated on a few episodes. Our results cast doubt on hopes that the private sector can serve as a meaningful bulwark against democratic erosion in the United States.

Pulling the Fire Alarm? Insurer corporate political behavior on climate change

Abstract

How do firms cross-pressured between energy transition risk and physical climate risk engage with climate politics? I hypothesize that cross-pressured firms will support climate adaptation policy as a way of reducing physical risk exposure without jeopardizing their carbon-intensive assets. Focusing on a most-likely case for the hypothesis, I examine one of the largest industries financially affected by rising climate risk: US property insurers. Large underwriting losses from climate shocks threaten industry profits and invite state intervention, seemingly creating large incentives to support decarbonization. Simultaneously, insurers are institutional investors in the carbon-intensive status quo, which confers transition risk. Linking a panel of insurer characteristics and security-level investment data with information on their lobbying and campaign contributions, I study how investments in fossil fuels (a measure of transition risk) and loss ratios on catastrophe-relevant underwriting (physical risk) affect insurer political behavior. Descriptively, insurers began lobbying on climate-related topics and realigned to support Democratic candidates after the 2017 climate-driven hardening to reinsurance markets. As predicted, most of the recent expansion of climate-relevant lobbying is on adaptation topics, rather than mitigation. Cross-sectionally, insurers’ exposure to catastrophe-relevant underwriting and fossil investments are associated with more and less climate-friendly political behavior, respectively. The findings contribute to growing literatures on insurance politics under climate change, firms’ responses to climate risk, and the politics of adaptation.

Who Pays for Climate Change? The Politics of Reinsurance Pools in the UK and Australia*

Abstract

Following climate-driven disruptions to property insurance in the last two decades, both the United Kingdom and Australia enacted public reinsurance pools, an emerging policy design that aims to stabilize insurance markets and which represents a blend of solidarity-based and market-based logic. However, despite these countries’ broadly similar political economies, their reinsurance pools differ in the form of risk socialization they enact and in the incorporation of private insurer preferences. Whereas in the UK private insurers preferred the Flood Re pool and virtually wrote its design, insurers all opposed the Cyclone Reinsurance Pool in Australia. Through a mixed methods approach drawing on semistructured elite interviews, analysis of government documents, and climate hazard data, I argue this variation owes to differences in (1) climate risk incidence, or the relationship between spatial climate risk and wealth; and (2) the institutional and structural power of the insurance industry.

Teaching

17.20 Introduction to American Politics

Fall 2024 with Professor Devin Caughey

17.802 Quantitative Research Methods II: Causal Inference

Spring 2025 with Professor F. Daniel Hidalgo