His research applies the growing field of network science to the study of neighborhoods, street gangs, gun violence, and police misconduct. He is also completing a book on the history and evolution of black street gangs and politics in Chicago. His writing has appeared in The American Journal of Sociology, The American Sociological Review, The American Journal of Public Health, JAMA Internal Medicine, Social Science & Medicine, Foreign Policy, The Annals of the American Academy of Social and Political Science, The Washington Post, The New York Times, and The Chicago Tribune.