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The impact of Mexican migration to the U.S. on urban crime rates


Our program trainee, Aaron Chalfin has recently completed an analysis of the impact of migration from Mexico to the United States on city-level crime rates. There is considerably debate regarding the effects of immigration on regional crime rates with conflicting claims; some finding large impacts of immigration on crime and some finding that a large immigrant population reduces crime rates. A key issue in this literature concerns the fact that immigrants may choose to locate in cities with moderate crime rates, thus creating a simultaneous relationship between the presence of immigrants and crime rates. Chalfin’s innovation is to make use of whether shocks in Mexico to isolate quasi-random variation in migration from Mexico to U.S. cities. He finds that in response to adverse weather shocks (either too little or too much rain), one can observe notable increase in migration from rural Mexico to key Mexican -receiving cities. Using this variation, Chalfin finds mixed evidence, with increases Mexican migration causing a significant decline in sexual assault but a significant increase in motor vehicle theft.

Address Goals

The project identifies a new source of variation in migration flows that will form the basis for a number of studies of the effects of immigration on receiving nations. This is a key methodological problem in this research, and Chalfin’s work will likely be well received and influential. The project has also made a real advance in the econometric analysis of regional crime rates.