"Butcher and Piehl were the first to show that immigrants are less likely to commit criminal offenses than natives (Butcher and Piehl, 1998a) and that, conditional on demo-graphic characteristics, immigrants are less likely to be incarcerated (Bucther and Piehl 2007). Analyzing a panel of metropolitan areas, they show that there is no correlation be-tween immigrant population share and crime, controlling for city demographic characteristics(Butcher and Piehl, 1998b). More recently Martinez, Stonewell and Lee (2010) find a negative correlation between homicides and immigration across census tracts in the San Diego metropolitan area, while Chalfin (2014) instruments for migration using rainfall shocks in Mexico and finds no correlation between immigration from Mexican and crime in the US. Likewise, Spenkuch (2014) does not find evidence of a correlation between immigration and violent crime in US states over three decades, but he does find a positive, though statistically insignificant, association with property crime. On the other hand Chalfin (2015) find that an increase in Mexican immigration, instrumented by the size of Mexican birth cohort, is associated with lower property crime and higher aggravated assaults. Overall, this literature establishes that it is hard to find evidence of a positive relation-ship between immigration and crime in panel data."