Adam Soliman

Adam Soliman

Assistant Professor of Economics at Clemson University

Research

Work in Progress

Working Papers and Publications

Crime and (a Preference for) Punishment: The Effects of Drug Policy Reform on Policing Activity

The Journal of Law and Economics, 2022

Abstract: We still know very little about the incentives of police. Using geocoded crime data and a novel source of within-city variation in punishment severity, I am able to shed light on enforcement behavior. I find that in parts of a city where drug sale penalties were weakened, there is a 13% decrease in all drug arrests. There is no displacement of non-drug offenses. If offenders were significantly deterred by harsher penalties, as the law intended and Becker’s (1968) model predicts, drug arrests should have increased in areas with weaker penalties. My results are therefore consistent with police treating enforcement effort and punishment severity as complements. I also find that city-wide crime and drug use do not increase after the reform. This paper thus calls into question the “War on Drugs” view of punishment and suggests that certain types of enforcement can be reduced without incurring large public safety costs.

Disrupting Drug Markets: The Effects of Crackdowns on Rogue Opioid Suppliers

American Economic Journal: Economic Policy, Conditionally Accepted

ASHEcon Program Chair Award (2023)

Abstract: This paper estimates the impacts of doctor crackdowns on the quantity demanded of prescription opioids, across-market substitution, and across-product substitution. Exploiting plausibly exogenous variation in the timing and location of administrative actions, I find that cracking down on a single doctor decreases county-level opioid dispensing by 10%. This decline persists across space and grows over time. Additionally, significant heroin substitution occurs, yet overall overdose mortality decreases. These results highlight a critical tradeoff policymakers should consider with targeted crackdowns: reductions in the flow of new users must be balanced against the harm that arises when existing users substitute to more dangerous drugs.

Prescriptive Drought Policy and Water Supplier Compliance

Ecological Economics, 2022

Abstract: Governments often cannot use prices to induce water conservation, and the need to understand the impacts of alternate methods is growing due to increased variability in water resources. During the 2012-2016 drought in California, a period that may presage the future of water management in a warmer climate, the state attempted to manage water use through a set of mandatory restrictions that assigned each of California’s 412 largest urban water suppliers to one of nine conservation tiers; those with greater historic usage needed to conserve more. I find that even though significant statewide savings occurred, only half of all suppliers complied with their conservation target. Moreover, the increased savings were not caused by the tiered design of the mandate: evidence from a regression discontinuity design shows that suppliers that just missed a stricter conservation tier actually conserved more. Additionally, water use rebounded after the regulation was removed, implying that variable adjustments in demand contributed more to water use savings than fixed cost household investments. Given the significant costs of water regulation and the high probability of future droughts, the policy implication is that both governments and water suppliers may benefit from investments in water supply reliability and less complex prescriptive policies.

The Social Spillovers of Homeownership: Evidence from Institutional Investors (with Steve Billings)

The News & Observer, WFAE 90.7/NPR

Abstract: Owning a home still represents the fulfillment of the American dream, but there continues to be disagreement about the role of government in promoting homeownership. The crux of the debate centers on the potential social benefits of homeownership, and we provide new evidence on these social spillovers by exploiting a recent trend of institutional investors purchasing single-family homes and converting them to permanent rentals. Using a granular spatial difference-in-difference design that centers on a single investor conversion to rental, we find that neighboring property values decline by 2%. These same neighboring properties experience declines in property maintenance and voting and increases in crime. While we observe that neighborhood compositional change is an important driver of these negative spillovers, property management appears to be the main source. Therefore, policies focused on building code enforcement and limiting lower quality property management may mitigate the negative spillovers from the drop in homeownership rates in America since the Great Recession.

Resting Papers

Rebel Funding Strategies: Illicit Activities, Natural Resources, and Substitution Behavior

Abstract: Rebel groups often exploit natural resources in order to finance their operations, yet we still know little about their basic funding decisions. Given the prevalence of asymmetric warfare, I examine how rebel groups choose between funding strategies using a unique panel dataset on the activities of 297 groups. I find that when the world price of a natural resource they exploit rises, rebel groups substitute away from extortion, smuggling, kidnapping, and theft. These results suggest that policies attempting to shut down these groups by cutting their main sources of funding may produce harmful unintended consequences in the short run.

Other Writing

Evaluation of Durham’s ShotSpotter Installation: Results of a 12-Month Pilot Project (with Phil Cook), Wilson Center for Science and Justice at Duke Law, February 2024

Corporate landlords are eroding the American Dream of homeownership, London School of Economics, Phelan US Centre, December 2023

Reducing the Costs of Drought: Lessons from Australia, Public Policy Institute of California, September 2015

What if California’s Drought Continues, Public Policy Institute of California, August 2015

The ‘Inexact Science’ of Water Pricing, Public Policy Institute of California, July 2015