Gratton, Brian, and Emily Merchant. 2013. "Immigration, Repatriation, and Deportation: The Mexican-Origin Population in the United States, 1920-1950." International Migration Review, 47(4): 944-975.
Scholars conventionally assert that government authorities forcibly expelled 500,000 persons of Mexican origin from the U.S. in the 1930s, with more than half of those removed U.S. citizens. Estimates using census data indicate substantially lower numbers, limited governmental involvement, fewer citizens, and considerable voluntary departure. Voluntary decisions fit the repatriation strategy that had been common among young Mexican immigrants in the 1920s. Ironically, the 1940s Bracero Program, designed by Mexico and the U.S. to replicate the 1920s pattern of circular migration, led instead to massive illegal immigration and unprecedented levels of deportation.