Brennan’s research focuses on criminal justice policies and systems and employment and training programs. Brennan specializes in the implementation of large-scale studies in collaboration with researchers, policymakers, and practitioners, conducting qualitative data collection and analysis as well as quantitative analysis. Her current projects include the Pretrial Justice Collaborative (PJC), the Los Angeles County Reentry Integrated Services Project (LA CRISP), and Building Evidence on Employment Strategies (BEES). Brennan earned a bachelor’s degree from Oberlin College and a master’s in public administration with a specialization in public policy analysis from New York University’s Wagner School.