Professor Leachman's research examines how the interaction between law and social movements affects patterns of inequality and social change. Much of her recent work investigates how impact litigation has affected the LGBT movement, including the power dynamics among LGBT movement organizations, public perceptions of the LGBT movement, and the compatibility of the mainstream movement's goals with the more underrepresented segments of the LGBT community. She is currently working on comparative projects that investigate how litigation shapes the strategies, goals, and outcomes of social movements of various types.