Modern humans with their inventive weaponry, during violent conflicts with Neanderthals and other indigenous populations of archaic humans; supposedly allowed early modern humans to wipe out other hominin species as they spread out of Africa. This ‘genocidal’ view is at odds with ‘horniness theory’ that interbreeding and inbreeding were major factors in the extinction of the Neanderthals. Of course to not discount the fall-back explanations of disease and climate change.
Most likely, the International Court of Justice will probably not be holding public hearings concerning the accusation of genocide against Neanderthals.