Not so long ago, migration between Mexico and the United States followed a circular pattern, whereby migrants moved regularly between the two countries, chasing seasonal jobs. But recent research published in the Journal of Ethnic and Migration Studies finds that immigration policies—and the militarization of our Southern border—have disrupted this pattern, effectively caging in undocumented immigrants rather than keeping them out as intended.
Throughout much of the 20th century, scores of laborers would arrived with six-month work visas in hand as part of the Bracero Program, working in the U.S. for half the year before returning home to Mexico. When the program ended in 1964, migrants continued to circulate between the two countries undocumented. Then in 1986, the U.S. Congress passed the Immigration Reform and Control Act, which cracked down on undocumented hiring and increased the number of border patrol officers.
For every million-dollar increase in budget, the odds a migrant would return home to Mexico in any given year dropped by 89 percent.
In the two decades preceding the passage of IRCA, as many as 85 percent of undocumented arrivals were offset by departures, according to the authors. Afterwards, the undocumented population in the U.S. steadily climbed, reaching a record 12 million in 2008.
Using survey data from the Mexican Migration Project, the team of researchers from Princeton University and Mexico's University of Guadalajara calculated the probability of in- and out-migration across the border by Mexicans over time. Before 1986, the probability of returning to Mexico from the U.S. was high for both legal and undocumented migrants. After that, the likelihood of return migration rose for documented migrants, but fell for undocumented workers, according to the analysis.
The study found that, by 2010, the probability of undocumented migration fell to an all-time low, but, the authors emphasize, "it is definitely not because of the increased US border enforcement, which had no significant effect on the likelihood of taking a first undocumented trip"—that is, the initial trek from Mexico to the U.S. Instead, the authors attribute the decline to the rising age of the Mexican population, and the falling labor demand in the U.S., among other things.
The study did find a correlation between the border patrol's budget and the likelihood that migrants would return home to Mexico, however. For every million-dollar increase in budget, the odds a migrant would return home to Mexico in any given year dropped by 89 percent. So border enforcement policies have actually backfired, it seems, resulting in a net increase in undocumented migrants in the U.S.
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