This Sunday's Guardian tells us of an effort by This is Ecocide to get the UN to recognize a fifth form of crime against humanity. They call the new crime "ecocide". On their solution page, Ecocide tells us that "ecocide can be the outcome of external factors, such as flooding or an earthquake".
If an earthquake occurs, I'm guessing the Earth's tectonic plates are to blame. It's not clear how any criminal group could cause an earthquake and then be prosecuted for it. Maybe if they did it with a thermonuclear weapon, but we already have laws against letting off thermonuclear weapons. If a flood occurs, I'm guessing it's the weather that's to blame. It's not clear how any criminal group could be prosecuted for that.
But they must have had someone in mind when they said a flood could be ecocide. What did they have in mind? What if a group of people prevent, by deliberate misinformation, the passage of laws that would otherwise have prevented the flood? What if a group of climate skeptics prevented the passage of a law that would reduce carbon dioxide emissions? Would they be guilty of ecocide?
I don't think the ecocide law would work well with the US constitution.
UPDATE: Is the volcanic eruption in iceland an act of ecocide, and if so, who is responsible?