This paper examines the definition of war crimes of conscripting or enlisting children under the age of fifteen years and using them to participate actively in hostilities. The focus is on the statutory framework and jurisprudence of the International Criminal Court. In the Lubanga case, the above-mentioned definition was construed with multiple references to human rights law. The common thread running through this paper is the relative weight given to international humanitarian law and human rights law by the International Criminal Court. It is submitted that the role of international criminal law and international humanitarian law is decisive in the Lubanga case, and rightly so. At the same time, references to human rights law merely confirm and legitimate the conclusions reached on other grounds rather than humanise the relevant international criminal law norms.