The mandating of universal jurisdiction by the grave breaches provisions of the 1949 Geneva Conventions was an innovation in relation to both the penal provisions of prior treaties and the prevailing understanding of the international legal basis for national jurisdiction over war crimes. Despite not having been relied on until the 1990s to ground national prosecutions on the basis of universality, the grave breaches provisions have exerted an influence on the development of both treaty-based and customary rules on universal jurisdiction. In some respects, however, this influence has been as an example of how not to draft jurisdictional provisions in international criminal law conventions.