For decades, hundreds of thousands of migrants have attempted to enter the United States through the country’s southern border. These individuals have made the journey to escape conflict and violence, poverty and a lack of economic opportunity, or to reunite with loved ones, among other reasons. In recent years, many of these individuals have crossed the U.S.-Mexico border to seek asylum. However, other migrants travel as clandestine migrants and attempt to avoid detection. These clandestine migrants take dangerous routes and face various obstacles throughout their journeys, whether by land or by sea. While clandestine migrants traverse the entire U.S.-Mexico border, this report focuses on their movement through the California borderlands.

In particular, this report seeks to answer three research questions related to clandestine migration: 1) How do clandestine migrants transit through California’s borderlands? 2) What are the risks to migrants during their journeys? and 3) Who are the individuals that facilitate clandestine migration in California? To answer these questions, we use a mixed methods approach. We rely on two original datasets—the Smuggling Incident dataset and the Migrant Testimony dataset—that examine the different migration phases, migrants’ experiences during their journeys, and migrant smugglers’ demographics. Additionally, we rely on three migrant death datasets from the Border Patrol, the San Diego County Medical Examiners’ Office, and the Imperial County Coroner to understand the risks for migrants during each clandestine activity. Finally, to supplement this information, we conducted 11 interviews with federal and local law enforcement, journalists, academics, and civil society organizations.