An international law of ecocide would make corporate CEOs and heads of state legally responsible for their destruction of Earth. People and planet would come before profits. (See the video below.) Of course, it will be a big help if we can get the economics right, requiring corporations to internalize the cost of social and environmental damages they cause, which they are now allowed externalize (one example of indirect subsidies to these companies), before pocketing their profits. A simple change to the corporate charter everywhere would level the playing field — and make ecocide economically fatal.
And to get a sense of the type of destruction Polly Higgins is referring to, watch this trailer for the four-segment movie, Fever, by LifeMosaic. It's a four and a half minute heartbreaker.