A study by researchers at Carnegie Mellon University and the University of Colorado-Boulder found that most communities in Mexico send migrants to specific U.S. destinations, and that communities with stronger ties to Arizona saw decreased emigration and increased return migration. Researchers concluded this was the result of the Legal Arizona Workers Act (LAWA), which requires all Arizona employers to use E-Verify.
A press release for the study said, "For the first time, our study shows that state-level immigration restrictions in the United States were effective in deterring the flow of unauthorized migrants into this country. Previous research had shown that state-level employment restrictions reduced the size of a state's population of likely unauthorized individuals, but it wasn't clear whether enforcement diverted migrants to other U.S. destinations or if these policies slowed international migration."
The researchers tracked geographic migration using data from a Mexican program that gives identification cards to Mexican migrants in the U.S. and other data from the U.S. and Mexican census bureaus. This enabled researchers to determine where migrants lived in the United States and where they were born in Mexico. The data showed the migrants living in different states often came from different parts of Mexico.
Using this information, the researchers then examined the LAWA's effect on migration. They compared Mexican locations where migrants favor Arizona as their destination to locations where migrants go elsewhere in the United States. The communities that favored Arizona experienced increased return migration from the United States and decreased emigration to the United States.
"Our findings show that labor-market interventions such as the E-verify program can affect international migration patterns, leading to a reduction in the total number of unauthorized migrants in the United States."
