At many moments in history, humanity’s propensity for wanton destruction has demanded legal and moral restraint. One of those times, seared into modern consciousness, came at the close of World War II, when Soviet and Allied forces liberated the Nazi concentration camps at Auschwitz and Dachau. Photographs and newsreels shocked the conscience of the world. Never had so many witnessed evidence of a crime so heinous, and so without precedent, that a new word—genocide—was needed to describe it, and in short order, a new framework of international justice was erected to outlaw it.

Another crime of similar magnitude is now at large in the world. It is not as conspicuous and repugnant as a death camp, but its power of mass destruction, if left unchecked, would strike the lives of hundreds of millions of people. A movement to outlaw it, too, is gaining momentum. That crime is called ecocide.

Pope Francis, shepherd of 1.2 billion Catholics, has been among the most outspoken, calling out the wrongdoing with the full force of his office. He has advocated for the prosecution of corporations for ecocide, defining it as the damage or destruction of natural resources, flora and fauna or ecosystems. He has also suggested enumerating it as a sin in the Catechism of the Catholic Church, a reference text for teaching the doctrine of the faith.

President Emmanuel Macron of France, too, has been sharply vociferous. He has called the burning of the Amazon’s rainforests an ecocide and blamed Brazilian President Jair Bolsonaro for reckless mismanagement of a planetary resource. Indigenous leaders have gone further. They have formally requested the International Criminal Court to investigate Bolsonaro for crimes against humanity. Ecocide is not yet illegal. International lawyers are working to codify it as a fifth crime but their campaign faces a long and uncertain road, riddled with thorny issues. 

Resource extraction and pollution of the commons power the beating heart of global economic prosperity. Practices that destroy Earth’s ecosystems—drilling, trawling, mining, logging, fertilizing, producing power, and even heating, cooling and driving—are ubiquitous. To prosecute and imprison political leaders and corporate executives for ecocidal actions, like Bolsonaro’s, would require a parsing of legal boundaries and a recalibration of criminal accountability. 

The moral power of advocates is increasing with the advance of environmental destruction. They already have much admissible evidence to make a case for placing limits on behaviors that make planetary matters worse. The Arctic is disappearing. Ice sheets in Greenland and Antarctica are melting. The jet stream is wobbling. The Gulf Stream is weakening. From a single degree Celsius of warming, an unfathomable amount of excess energy is now trapped on the planet and wreaking havoc on the reliable seasonal rhythms that have sustained human life for millenia.

Scientists are in agreement that worse is yet to come. The most vulnerable are the most in harm’s way. Relentless droughts and Biblical floods, storms of greater ferocity and frequency, sea level rise, crippling heat and uncontainable wildfires all forcing the unprecedented displacement of entire human populations fleeing for their lives. 

The litany is familiar, already true and accelerating.  But half a century after the problem was clearly identified, no one and no entity can yet be held responsible for climate change, the largest ecocide of all. 

The idea of ecocide is a cri de coeur for accountability against all odds. Many years of a plodding process lie ahead of the International Criminal Court, before its 123 member nations can agree to prosecute the crime, and in the end, they may decide not to. Even if they do agree, the United States and China, the world’s biggest polluters, are not signatories to the treaty that established the Court and do not recognize its jurisdiction, legitimacy or authority to prosecute genocide, let alone ecocide.

The effort to criminalize ecocide is an enormously significant story of our time. Over the next months, in partnership with NBC News, we will be reporting on this next frontier of international law. We will also be examining environmental destruction from the perspective of ecocide and watching to see if new legal and moral restraints will help to slow the progress of the planetary catastrophes that loom ahead.