He received a Ph.D. from the University of Chicago in 2001 and is the author of Freedom or Security: The Consequences for Democracies Using Emergency Powers to Fight Terror (Praeger, 2003), the co-editor of Gangs and Guerrillas: Ideas from Counterterrorism and Counterinsurgency, the editor of Financing Terrorism: Case Studies (Ashgate 2012), as well as the author of several journal articles and book chapters on terrorism, emergency powers, and terrorist financing.