Police Safety, Killings by the Police, and the Militarization of US Law Enforcement

Journal of Urban Economics (2021)


The debate over police use of military equipment often revolves around the supposed trade-off between increasing police safety and reducing killings by the police. In this paper, I rely on institutional features that exogenously determine the distribution of military equipment to US police departments to show that, contrary to previous evidence, there is no such tradeoff: police militarization increases killings by the police and reduces police safety. Each year police militarization results in 64 additional killings by the police, 12,440 police officer assaults, and 2,653 police officer injuries.

State, Religiosity and Church Participation

Journal of Economic Behavior & Organization (2021)


In the last generations most of the Western world has faced rapid secularization combined with large expansions in the welfare state. At the same time, many other countries have maintained high levels of religiosity and a more limited role for the state. I propose a model of intergenerational transmission of religious values and competition between the state and the church that shows how an increase in state efficiency can trigger this process of secularization and rise of the welfare state. At the same time, I show that this initial increase in state efficiency can be hard to attain. Due to the competition between the church and the state, agents may have incentives to sabotage the efficiency of the state, preventing the start of the secularization process. Finally, I provide empirical evidence in line with this model and show that consistent empirical results are only present when focusing on areas of the state that are in direct competition with the church.

Violent Crime and the Overmilitarization of US Policing

Journal of Law, Economics, & Organization (2021)

Manuscript - Appendix

Using new data at the police department level, I propose an identification strategy for estimating the causal effect that police militarization has on reducing violent crime. I show that previous estimates are likely to be contaminated by unobserved factors that simultaneously determine militarization and violent crime. Upon addressing this issue, I find a point estimate that is 20 times larger than those estimated previously. I then find that one-fourth of the effect of militarization is due to the displacement of violent crime to neighboring areas. Police departments overmilitarize because they do not consider this externality. These new findings have significant implications for the policy debate concerning the costs and benefits of police militarization.

Working Papers

The Charitable Terrorist: State Capacity and the Support for the Pakistani Taliban (with Hasin Yousaf)

R&R Journal of Conflict Resolution

Manuscript - Appendix

In the media: UNSW Newsroom

Violent, criminal, and terrorist organizations are often providers of many social services in direct competition with the state. In this paper, we show that these organization can use the provision of social services to gain support. This tactic is only effective when filling the void left by a weak state. We do so by studying the provision of natural disaster relief by the Pakistani state and the Taliban. We first look at the floods of 2010 that received an inadequate response from the government and show that support for the Taliban increased in the areas affected by the flood. These effects are concentrated in places were the Taliban likely provided help and where the state under-delivered the most. We then study an earthquake in 2005 that instead received a swift government response and show that the Taliban lost support in the areas affected. Alternate mechanisms such as anger against the incumbent, political competition, electoral participation, and religiosity do not account for these results.

Flight from Urban Blight: Lead Poisoning, Crime and Suburbanization (with Federico Curci)

R&R The Review of Economics and Statistics

Manuscript - Appendix

In this paper we study the effect of violent crime on residential and firms location decisions and their implications for segregation in cities. We do so by proposing a new instrument to exogenously predict violent crime in city centers. We base our instrument on chemical evidence that links local characteristics of the soil to lead poisoning, and medical results on the effect of lead poisoning on aggression. In particular, we exploit the national increase of lead poisoning in the United States in the post-WWII period, to compare cities with different levels of pH of city center soil that determines lead bioavailability. Using data from 325 U.S. cities, we show that the massive increase in violent crime experienced by city centers between 1960 and 1990 moved almost 26 million people to the suburbs. Firms followed by leaving the city centers and moving to the suburbs. We then show that the suburbanization process was characterized by "white flight". As city centers became more violent, white rich people moved to the suburbs while poor and black people stayed in the city center. This increase in violent crime is still shaping segregation in U.S. cities today, although violent crime in city centers has returned to lower levels.

Pains, Guns and Moves: The Effect of the US Opioid Epidemic on Mexican Migration (with Gianmarco Daniele and Marco Le Moglie)

R&R Journal of Development Economics


The opioid epidemic and migration along the US--Mexico border are two of the most-debated policy issues in recent US politics. We show how these two topics are interlinked: the US opioid epidemic generated large Mexican migration flows. We exploit the fact that in 2010, a series of reforms to the US health care system resulted in a shift in demand from legal opiates to heroin. This demand shock had considerable effects on Mexico, the main supplier of heroin consumed in the US. Violence and conflicts increased in Mexican municipalities suitable for opium production, as they became highly valuable to drug cartels. People migrated out of these municipalities to escape this violence, mostly to areas close to the US border and into the US. The rise in US demand for heroin increased internal migration by an estimated 90,000 individuals and migration across the border at least by 12,000.

Whistle the Racist Dogs: Political Campaigns and Police Stops (with Pauline Grosjean and Hasin Yousaf)

Reject & Resubmit The Quarterly Journal of Economics


In the media: Promarket - LeMonde - VoxEU

Did Trump rallies aggravate anti-Black racism? Using data from nearly 12 million traffic stops, we show that the probability that a police officer stops a Black driver increases by 5.1\% after a Trump rally during his 2015-2016 campaign. The effect is immediate, specific to Black drivers, lasts for up to 50 days after the rally, and is not due to changes in drivers' behavior. The effects are significantly larger among racially biased officers, in areas with more racist attitudes today, that experienced more racial violence during the Jim Crow era, or that relied more heavily on slavery. Results from a 2016 online experiment show that Trump's inflammatory campaign speech, although not explicitly mentioning Black people, specifically aggravated respondents' prejudice that Black people are violent. We find that the same words also increase the effect of a Trump rally among racially biased officers. We take this as evidence that although not explicitly anti-Black, Trump's campaign radicalized racial prejudice against Black people -- through a phenomenon known as dog-whistling -- and the expression of such prejudice in a critical and potentially violent dimension: police behavior.

Contagious Dishonesty: Corruption Scandals and Supermarket Theft (with Giorgio Gulino) Submitted


In the media: OCCRP - Corriere dell'Alto Adige - Nada Es Gratis - Bribe, Swindle or Steal

Is dishonest behavior contagious? We answer this question by studying whether corruption scandals affect the propensity of supermarket customers to steal while using a self-service checkout system. Crucially, this system provides shoppers with the opportunity to engage in dishonest behavior by under-reporting the value of their shopping cart. Exploiting data from random audits on shoppers, we show that the probability of a shopper under-reporting increases by 16% after a local corruption scandal is made public. The effect starts immediately and is particularly strong during the first four days after the story breaks. This effect is not driven by any change in material incentives or social norms. Rather, we show that it is due to a reduction in the self-imposed moral cost of stealing and is mainly concentrated among taxpayers.

Tell Me What You Grow and I'll Tell You What You Think: Westward Expansion and the Politics of Slavery in the US South (with Michele Rosenberg)


Slavery had long been one of the dominant labor institutions before its demise in the nineteenth century. This paper shows that changing economic interests determined shifts in political support for slavery. We exploit the competitive forces generated by the westward territorial expansion of the Southern United States between 1810 and 1860 to identify changes in local economic incentives for the use of slave labor. We show that areas losing their comparative advantage in the production of cotton relative to wheat changed their production decisions and reduced their use of slave labor. Evidence suggests that economic benefits for the white laborers and the political influence of the planter elite sustained a broad pro-slavery coalition. The local decline of slavery profitability decreased wages and shifted newspapers' pro-slavery content, reducing non-slave-owners’ incentives to support the institution. The paper shows that the Westward Expansion divided the South's productive, political, and social systems in the decades leading to the Civil War.

Published Papers (Pre-PhD)

How Informative are the Subjective Density Forecasts of Macroeconomists? (with Geoff Kenny and Thomas Kostka)

Journal of Forecasting (2014)


In this paper, we propose a framework to evaluate the subjective density forecasts of macroeconomists using micro data from the euro area Survey of Professional Forecasters (SPF). A key aspect of our analysis is the use of evaluation measures which take account of the entire predictive densities, and not just the probability assigned to the outcome that occurs. Overall, we find considerable heterogeneity in the performance of the surveyed densities at the individual level. However, it is hard to exploit this heterogeneity and improve aggregate performance by trimming poorly performing forecasters in real time. Relative to a set of simple benchmarks, density performance is somewhat better for GDP growth than for inflation, although in the former case it diminishes substantially with the forecast horizon. In addition, we report evidence of an improvement in the relative performance of expert densities during the recent period of macroeconomic volatility. However, our analysis also reveals clear evidence of overconfidence or neglected risks in expert probability assessments, as reflected in frequent occurrences of events which are assigned a zero probability.

Density Characteristics and Density Forecast Performance: a Panel Analysis (with Geoff Kenny and Thomas Kostka)

Empirical Economics (2015)


In this paper, we exploit micro data from the ECB survey of professional forecasters to examine the link between the characteristics of macroeconomic density forecasts (such as their location, spread, skewness, and tail risk) and density forecast performance. Controlling for the effects of common macroeconomic shocks, we apply cross-sectional and fixed effect panel regressions linking such density characteristics and density forecast performance. Our empirical results suggest that many macroeconomic experts could systematically improve their density performance by correcting a downward bias in their variances. Aside from this shortcoming in the second moment characteristics of the individual densities, other higher moment features, such as skewness or variation in the degree of probability mass given to the tails of the predictive distributions, tend—as a rule—not to contribute significantly to enhancing individual density forecast performance.

Can Macroeconomists Forecast Risks? Event-based Evidence from the ECB SPF (with Geoff Kenny and Thomas Kostka)

International Journal of Central Banking (2015)


We apply methods to evaluate the risk assessments collected as part of the ECB Survey of Professional Forecasters (SPF). Our approach focuses on direction-of-change predictions as well as the prediction of more specific high and low macroeconomic outcomes located in the upper and lower regions of the predictive densities. For inflation and GDP growth, we find such surveyed densities are informative about future direction of change. Regarding high and low outcome events, the surveys are most informative about GDP growth outcomes and at short horizons. The upper and lower regions of the predictive densities for inflation appear less informative.