Research

This paper examines how incarceration and probation shape community crime rates with 20 years of administrative court records from Milwaukee, Wisconsin. I estimate causal effects by instrumenting for a criminal defendant's sentence with the preferences of a randomly assigned judge. I extend the canonical randomized judge design framework to incorporate effects generated along the intensive margin of sentence durations. This framework allows me to distinguish between effects to the marginally incarcerated defendant from effects to non-marginal defendants. Empirically, I find that longer sentences reduce defendant recidivism for both probation and incarceration. For the marginal defendant, this may lead to offsetting dynamics on the margin of incarceration. At the neighborhood level, however, only incarceration generates crime-reducing spillover effects in nearby households. I provide evidence that these effects are driven by the incapacitation of high severity offenders. 

The United States is one of the few OECD countries to pay individuals to donate blood plasma and is the most generous in terms of remuneration. The opening of a local blood plasma center represents a positive, prospective income shock for would-be donors. Using detailed data on the location of blood plasma centers in the US and two complementary difference-indifferences research designs, we study the impact of these centers on crime outcomes. Our findings indicate that the opening of a plasma center in a city leads to a 12% drop in the crime rate, an effect driven primarily by property and drug-related offenses. A within-city design confirms these findings, highlighting large crime drops in neighborhoods close to a newly opened plasma center. The crime-reducing effects of plasma donation income are particularly pronounced in less affluent areas, underscoring the financial channel as the primary mechanism behind these results. This study further posits that the perceived severity of plasma center sanctions against substance use, combined with the financial channel, significantly contributes to the observed decline in drug possession incidents.