Naturalization of US immigrants: Why citizenship rates differ by state

This paper attempts to shed light on an often under-researched topic in the immigration literature, and that is: what influences the decision of immigrants to become naturalized.  Applying for citizenship is not obligatory for someone who has received permanent residency status. Rather, it is a voluntary and optional final step that an immigrant chooses to take.  In particular, we investigate the extent to which the geographic region in which an immigrant resides influences the propensity to naturalize by specifically analyzing the variation in U.S. immigrant citizenship rates across states. By merging Census data with other forms of publically available state level data, we are able to better understand why state naturalization rates in the U.S. vary so dramatically, from a low of about 30% to a high of almost 60%. We find that while applying for citizenship is an individual decision, both institutional and group variables influence this decision. Consistent with prior research, our results indicate that a more favorable economic environment is correlated with higher naturalization rates and that the clustering of Mexicans discourages naturalization. Unique to the literature, our results also indicate that states that are more socially and politically welcoming to immigrants have statistically higher rates of naturalization, and that there are no significant negative effects on naturalization rates in states with larger numbers of undocumented immigrants. Our research contributes to the growing body of literature on naturalization decisions and supports the proposition that attitudes towards immigrants, be they authorized or undocumented, influence the extent to which the foreign born become fuller participants in U.S. society.