| his dissertation considers the role that of various inputs in informing the market for crimes. Chapter 1 considers the "national" effect of immigration. Using panel data on U.S. cities and an instrument that leverages temporal variation in rainfall in different regions of Mexico and persistence in regional Mexico-U.S. migration networks, my findings indicate that Mexican immigration is associated with no appreciable change in the rate of either violent or property crimes in U.S. cities.;Chapter 2 leverages a natural experiment created by recent legislation in Arizona to estimate the impact on crime of an extremely large and discrete decline in the state's foreign-born Mexican population. I show that Arizona's foreign-born Mexican population decreased by as much as 20 percent in the wake of the state's 2008 implementation of the Legal Arizona Workers Act (LAWA), a broad-based E-Verify law requiring employers to verify the immigration status of new employees, coupled with severe sanctions for employer noncompliance. In order to isolate the causal effect of the passage and implementation of LAWA on crime, I leverage a synthetic "differences-in-differences" estimator, using a new method of counterfactual estimation proposed by Abadie, Diamond and Hainmuller (2010). In contrast to previous literature, I find significant and large effects of Mexican immigration on Arizona's property crime rate. Results are driven, in large part, by the fact that LAWA resulted in especially disproportionate declines among Mexican migrants who are young and male and, as such, the effects are predominantly compositional.;The final chapter, coauthored with Justin McCrary, considers the responsiveness of crime to police manpower. Using a new panel data set on crime in medium to large U.S. cities over 1960- 2010, we show that (1) year-over-year changes in police per capita are largely idiosyncratic to demographic factors, the local economy, city budgets, measures of social disorganization, and recent changes in crime rates, (2) year-over-year changes in police per capita are mismeasured, leading many estimates in the literature to be too small by a factor of 5, and (3) after correcting for measurement error bias and controlling for population growth, a regression of within-state differences in year-over-year changes in city crimes on within-state differences in year-over-year changes in police yields economically large point estimates. Our estimates imply that each dollar spent on police is associated with approximately... |
