Relationship Goals: A Social Network Analysis of the Relationships between Bill Sponsors and Cosponsors on Immigration Legislation from 1973-2016

This dissertation contains three essays regarding relationships formed between members of Congress in the U.S. House and Senate. The primary focus is to determine how partisanship and polarization influence these decisions to cosponsor with others on these types of bills. The first chapter examines relationships between members of Congress on all immigration bills introduced between 1973 and 2016. The results indicate that there was a higher likelihood of bipartisanship on bills introduced until the mid-1990s when copartisanship was the predominate form of ties to present. In the second chapter, I analyze cosponsorship networks between members of Congress on the different types of immigration legislation introduced over a period of four decades to try and infer how these social relationships may influence behavior when it comes to supporting immigration policy that benefits or sanctions immigrants. The results in the House and Senate reveal that Republicans were more likely to cosponsor with other Republicans on immigration legislation that provided benefits, and Democrats were only more likely to form copartisan ties with one another on this subtype for four of the twenty-two terms—only consecutively so since 2011. For bills that limited immigrants or provided sanctions against them, Republicans in the House were overall more likely to work with other Republicans and Democrats were also more likely to cosponsor enforcement legislation with other Democrats an equal amount of the time. Finally, the third chapter investigates how race and ethnicity shaped the incentives of members to cosponsor different types of immigration legislation. The results provide evidence that members from majority-minority districts were more likely to form cosponsorship relationships with each other. Minority members were generally more likely to form relationships with other minority members on bills that benefit immigrants. However, being a Hispanic or having a higher percent of Hispanics in a congressional district made a little difference in forming relationships with each other. This research provides an important contribution to the existent literature that looks at the interdependencies of legislators through cosponsorship activities to shed light on how members of Congress work together on immigration policy during the pre-floor stages of the legislative process.