Internal migration and drug violence in Mexico

We study how internal migration responds to an increase in criminal violence in the context of Mexico’s 2007 War on Drugs. To identify causal effects, we exploit the changes in homicides generated by conflict between drug-trafficking organizations. Instrumental variable regressions show that high skilled individuals are less likely to migrate to a municipality where the homicide rate increased. Conversely, we find out-migration from municipalities that experienced an increase in murders but only to other municipalities in the same commuting zone. We interpret these facts as evidence that the migration response to increases in violence is tempered by moving costs. Using a discrete-choice model over destination choices, we estimate individuals would be willing to accept a reduction in wages of 0.15% to 0.58% to decrease the local homicide rate by 1%. The welfare cost of the post-2007 spike in homicides is in the order of 10% of GDP per year.