For more than 140 years, individuals have clandestinely crossed into the United States through Arizona. These migration routes often circumvent official ports of entry and expose individuals to the state’s harsh terrain, including extensive deserts and mountain ranges. In the summer, temperatures can soar well above 100 degrees Fahrenheit, while winter temperatures in the mountains can plummet to below freezing. These extreme conditions make the Arizona borderlands a treacherous and often deadly crossing zone for unauthorized migrants entering the United States.

This research report focuses on clandestine migration in Arizona and aims to address three key questions. First, how do clandestine migrants currently transit through the Arizona borderlands? Second, what are the associated safety risks for migrants? Third, who are the people arrested for engaging in migrant smuggling activities in Arizona? To address these questions, this report employs a mixed-methods approach. To identify routes, risks, and smuggler demographics, it uses two original datasets that document 119 migrant smuggling incidents and associated material witness testimonies from January 2014 to August 2024. To assess migrant risks and mortality, the report analyzes the Border Patrol’s Border Safety Initiative Tracking System (BSITS) migrant death records and recovered remains data from medical examiners in Pima County and Yuma County. It also relies on interviews with federal officials, civil society organizations, and scholars to fill in any gaps.