ABSTRACT
This chapter examines the effects of undocumented Mexican immigrants on the earnings of other workers in geographical labor markets in the Southwest. Both the volume and composition of immigration to the United States have changed considerably over the past 20 years. As a result of the National Immigration Act of 1965 and subsequent legislated admission of political refugees, the number of legal immigrants has reached levels nearly as great as those occurring early in the 20th century. Studies of the effects of undocumented immigration have been hampered because reliable data on the size and distribution of the illegal population in the United States have not been available until recently. As of 1980, Mexican immigrant workers made up nearly 50 percent of the low-skilled manufacturing labor force in the standard metropolitan statistical area. Prior empirical work has not disaggregated the Mexican immigrant population by period of entry or legal status.
