In this essay, Polly Higgins, Damien Short and Nigel South argue for supporting a law of ecocide as the fifth crime against peace under the Rome Statute. To arrive at this conclusion, the authors first exemplify environmental crimes, consider the responses calling for more effective models of justice and law, then trace the evolution of proposing ecocide as an international crime. In 2010, Higgins proposed an amendment to the Rome Statute, defining ecocide as “the extensive damage to, destruction of or loss of ecosystem(s) of a given territory, whether by human agency or by other causes, to such an extent that peaceful enjoyment by the inhabitants of that territory has been severely diminished.” Ultimately: “A law of Ecocide should recognise human-caused environmental damage and degradation (whether committed during or outside war-time), as a crime of strict liability (in other words, without intent).”