Sanctuary Policies and the Influence of Local Demographics and Partisanship

Despite the increased scholarship on sanctuary localities in the United States, there is little research analyzing the factors that lead to the adoption of sanctuary resolutions at the municipal level. Drawing on a new dataset of sanctuary and nonsanctuary cities, we theorize that policy adoption is driven primarily by two factors and their interaction: the size of the foreign-born population and local partisanship. We examine cities that passed sanctuary policies between 2000 and 2018 and compare these localities to nonsanctuaries. Using a novel time series cross-section dataset (TSCS) of all cities and designated places and a Cox proportional hazard model, we find that Democratic-leaning cities with high foreign-born populations predict sanctuary passage, whereas Republican-leaning cities with larger foreign-born populations are unlikely to adopt these policies. We thus find that while partisanship motivates sanctuary policy adoption, at the same time, the size of the foreign-born population also increases the likelihood of passage.