As of 2004 California employed almost 30% of all foreign born workers in the U.S. and was the state with the largest percentage of immigrants in the labor force. It also received a very large number of Mexican and uneducated immigrants during the recent decades. If immigration harms the labor...

Using the large variation in the inflow of immigrants across US states we analyze the impact of immigration on state employment, average hours worked, physical capital accumulation and, most importantly, total factor productivity and its skill bias. We use the location of a state relative to the...