9.       […] the Tribunal only has jurisdiction over a listed crime if that crime was recognised as such under customary international law at the time it was allegedly committed.[1] The scope of the Tribunal’s jurisdiction ratione materiae may therefore be said to be determined both by the Statute, insofar as it sets out the jurisdictional framework of the International Tribunal, and by customary international law, insofar as the Tribunal’s power to convict an accused of any crime listed in the Statute depends on its existence qua custom at the time this crime was allegedly committed.[2]

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18.     […] A crime or a form of liability which is not provided for in the Statute could not form the basis of a conviction before this Tribunal.[3] The reference to that crime or to that form of liability does not need, however, to be explicit to come within the purview of the Tribunal’s jurisdiction.[4] The Statute of the ICTY is not and does not purport to be, unlike for instance the Rome Statute of the International Criminal Court, a meticulously detailed code providing explicitly for every possible scenario and every solution thereto. It sets out in general terms the jurisdictional framework within which the Tribunal has been mandated to operate.