This article examines the phenomenon of accelerated formation of customary international law. It argues that in periods of fundamental change (which the author characterizes as "Grotian Moments"), whether by technological advances, the commission of new forms of crimes against humanity, or the development of new means of warfare or terrorism, customary international law may form much more rapidly and with less state practice than is normally the case to keep up with the pace of developments. The article examines several case studies that explore the application and contours of the concept of "Grotian Moments."


international law, customary international law, crimes against humanity, terrorism, international criminal law

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20 ILSA Journal of International & Comparative Law 305 (2014)

Publication Information

ILSA Journal of International & Comparative Law


COinS Michael P. Scharf Faculty Bio