  This paper estimates the impact of violence on domestic and international
migration in Mexico during 2005-2020. Unlike earlier studies, we use network
analysis to quantify changes in the degree of interconnectedness among all
municipalities in Mexico and with the US, breaking it down by
origin-destination pairs. To identify the impact of violence on the changes of
the migration network, we use instrumental variables. We exploit the exogenous
variation in heroin street prices in the US, local prices of corn in Mexico,
and differences in which regions received more Chinese immigrant communities
during the 1930s, members of which introduced opium cultivation and drug
smuggling networks in Mexico. These instruments help us identify the areas with
a current presence of drug trafficking organizations and facing increases in
violence. We show that municipalities that experience rises in homicide rates
continue to attract immigrants within the country, but they face a larger rise
in domestic emigration. The violence also discourages the return migration of
Mexicans from the US and non-transit international emigration. Consistent with
our findings, areas affected by violence also experience a long-term reduction
in vehicle trips made in the highway network connecting them with the rest of
the country.
