Josephine Wonsun Hahn

Josy Hahn is a senior research fellow and manager and social epidemiologist in the Brennan Center’s Justice Program, where she works to implement rigorous research and racial equity approaches in the criminal legal system.

Previously, Hahn was a research director of racial equity and fairness at the New York City Mayor’s Office of Criminal Justice. In that role, she led an innovative portfolio, launching officewide racial equity work, examining racial disparities in neighborhood health and the criminal legal system, and partnering with racial equity initiatives, such as the Mayor’s Action Plan for Neighborhood Safety and the Office to Prevent Gun Violence.

Prior to that, Hahn led numerous mixed-methods studies and reports at the Center for Court Innovation and the Vera Institute of Justice, examining system and community responses to alternatives to enforcement, restorative justice, gender-based violence, and neighborhood safety. Earlier in her career, she was a middle school history teacher at the Horace Mann School and worked with youth and families involved in the criminal legal system.

Hahn holds a BA from Princeton University, an MPH from the University of Medicine and Dentistry of New Jersey in Newark, and a PhD from the Harvard School of Public Health.