Racism and Discrimination. As already discussed, some minority groups have much higher arrest and incarceration rates than whites. Some assert that this fact may reflect bias in the criminal justice system. This is also something to consider when studying immigrant crime. Immigrants are overwhelmingly minorities; their arrest or incarceration rates may be impacted by biases throughout the criminal justice system. Moreover, even if immigrants do commit a disproportionate share of crime, it is worth considering the role that prejudices may play in the larger society. This could be a function of racism rather than a problem with the immigrants themselves.
A study of Italy before and after the January 2007 European Union enlargement found that giving legal status to the previously illegal immigrants from the new EU members states led to a "50 percent reduction in recidivism".  The authors find that "legal status... explains one-half to two-thirds of the observed differences in crime rates between legal and illegal immigrants".  A study on the 2007 so-called "click day" amnesty for undocumented immigrants in Italy found that the amnesty reduced the immigrant crime rate.  The authors estimate "that a ten percent increase in the share of immigrants legalized in one region would imply a percent reduction in immigrants’ criminal charges in the following year in that same region".  However, research also shows that stricter enforcement of migration policy leads to a reduction in the crime rate of undocumented migrants.