Higher union density in a state is a more powerful deterrent for unauthorized immigration than almost any other economic factor.
April 1, 2026
Original Paper
Migrating for Economic Freedom: Economic and Labor Freedom institutions and US State immigrant inflows
SSRN · 6408158
The Takeaway
While we typically assume immigrants move based on general economic opportunity, a 1% increase in state union density is associated with a massive 15.9% decrease in the unauthorized immigrant population. This suggests that the institutional gatekeeping and labor protections of unions are a far more effective barrier to unauthorized labor than standard market forces.
From the abstract
This paper examines how state-level institutions shape immigrants' location choices within a federal system. Social Scientists find that foreign-born immigrants migrate to areas with favorable economic conditions and labor markets, and that immigration is associated with positive economic outcomes. Strong economic and labor market institutions also correlate with positive economic outcomes. I show how state-level economic and labor market freedoms shape inflows of both unauthorized and legal for