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Build a bigger wall at the border?

Claude Fischer, professor of sociology | April 29, 2016

A key Donald Trump pledge is to stop the inflow of undocumented Mexican immigrants by building a border wall so much higher and wider than the one we have now that none could enter the U.S. illegally. One oddity of this pledge is that the inflow of undocumented Mexicans has already stopped. For the last roughly seven years, the illicit migration across our southern border has been zero or even negative.

There is another oddity about this proposal. From 1986 to 2008, the U.S. vastly boosted border control forces, technology, and barriers. Did this immense crackdown impede or slow down border-crossing? Not really. One thing it did do, however, was to increase – by about 4 million – the number of undocumented migrants who settled down in the U.S.

border wallThat is the conclusion of a comprehensive analysis recently published by Douglas Massey, Jorge Durand, and Karen Pren in the March issue of American Journal of Sociology, titled “Why Border Enforcement Backfired.”


Douglas Massey, an eminent sociologist widely recognized for his several major research contributions on critical social issues, has for over 30 years run the Mexican Migration Project. In that period, he and his associates surveyed nearly 24,000 households in 143 Mexican communities about the migration histories of their roughly 150,000 family members. The recent paper takes these data, combines them with various official statistics, and applies sophisticated statistical techniques to answer the question, What happened as the Border Patrol budget rose from under $500 million in the 1980s (measured in 2013 dollars) to nearly $4 billion in the 2010s?

Taking into account all sorts of other changes during those years, such as fluctuating wages in the U.S. and Mexico, violence in Mexico, rising educational levels, and the big drop in the Mexican birth rate–which is the major reason why the migration flow from Mexico has essentially ceased–Massey and colleagues isolated the effects of the 1980s-2000s enforcement boom.

* Beefing up border enforcement by an order of magnitude shifted where the migrants crossed into the U.S. Instead of breaching the border at urban locations such as San Diego and El Paso, they increasingly crossed over in much more remote places like desert areas of Arizona. Given that change, more migrants had to use “coyotes,” paid and not always reliable guides, and had to pay them more–up from about $550 a trip in 1989 to $2700 a trip in 2010.

And more would-be migrants died trying to enter the U.S. Migrant deaths rose from roughly about 100 to about 400 a year. Massey et al. estimate that the border crackdown cost an additional 5,000 lives. For Mexicans who got into the U.S. (which is most of those who tried), the crackdown, which made them more vulnerable and weakened their bargaining positions with employers, reduced the wages they earned in the U.S. Tougher border enforcement also forced the undocumented to work longer in the U.S. in order to earn the money for another roundtrip back to their homes and then back to the U.S. (more on such roundtrips below.)

* The increase in enforcement did increase the chances that migrants would be apprehended by the Border Patrol on their first tries to cross. In the 1970s, about 40 percent got caught in their first efforts, 20 percent were as the crackdown started in the 1980s, and again about 40 percent got caught in the late 2000s.

However, the border crackdown did not affect the chances that migrants would eventually cross after repeated tries. From the 1970s into the 2000s, a bit under 100 percent of family members who tried to enter the U.S. managed to do so. In the late 2000s, the percentage who eventually succeeded fell to about 75 percent, but “by then almost no Mexicans were attempting to cross in the first place.”

* Most critically for those concerned about the swelling population of undocumented residents in the U.S., the escalation of border enforcement reduced the flow of migrants already in the U.S. back to Mexico and then additionally reduced the numbers going back to the U.S. after that first return. Instead, the undocumented stayed on this side.

Earlier, when the border was more sieve-like, Mexicans would enter the U.S. to work during hiring seasons, such as fruit harvesting, and then return home for the off-season. However, “the border buildup prevented a continued high rate of return migration [to Mexico] that otherwise would have occurred….” Instead, migrants remained in the U.S., often arranging for family members to join them; many further settled in by moving north.

Thus, the border buildup “backfired by cutting off a long-standing tradition of migratory circulation and promoting the large-scale settlement of undocumented migrants who otherwise would have kept moving back and forth across the border” – adding what Massey et al. estimate as 4 million people to the undocumented population.


So, what about building “a great wall” that “just got ten feet higher“? Basically, it is  irrelevant because, given the drop in Mexican birth rates and the rise in the Mexican economy, there is no influx; “the boom in Mexican migration is likely over.”

However, were things to radically change or were Central American migration through Mexico become a subject of wide concern, a wall (perhaps paid for by Guatemala?) probably would – on the basis of past experience – not stop those determined to enter the U.S., but likely encourage those who do arrive to stay.

Cross-posted from Claude Fischer’s blog, Made in America: Notes on American Life from American History.