Her research work has focused on the roots of violence in people.

He covers criminal justice issues and is the author of All God's Children: the Bosket Family and the American Tradition of Violence

He has served on national task forces on violence and prevention and directs a longitudinal study of youth from age 8 to young adulthood. The study focuses on identifying early risk factors for adolescent disorders, particularly involvement in violence and antisocial behavior.

He assisted the Council on Crime in America in drafting its new report, "Saving Children, Preventing Crime."

He is the city's chief juvenile prosecutor and is the author of articles and opinion pieces on juvenile violence and justice, and of Killer Kids, Bad Law.

He is Director of Research at the Institute of Juvenile Research and a principal investigator on several scientific studies on violence and related social problems among children and adolescents. His research work has focused on the evaluation of prevention programs and on issues related to the development of urban children and families.