The definition of ecocide she proposed was the mass "damage, destruction or loss of ecosystems 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".
The size, duration and impact of ecocide could be measured by the international laws applied during wartime. Ecocide was committed if the size of the affected area exceeded 200km in length, had an impact on ecosystems for more than three months and had a severe impact on human or natural resources.
Higgins suggested lignite mining in Southland and proposed deepwater drilling in the Great South Basin could qualify as New Zealand examples of ecocide because they would create enormous greenhouse gas emissions.
Her proposed legislation has gained significant interest since the BP Deepwater Horizon oil spill last year, the United States' worst environmental disaster.
Higgins said at present, BP had no onus to protect the environment because legal systems treated all that was not human as property. She believed the world needed to shift from the property law model to a trusteeship model.
Much of the "hardware" was already in place in the form of the ICC, the United Nations, and the international laws of crimes against peace and the human right to life.
Her seminar cited United Nations research from 2008 which showed that the world's top 3000 corporations caused $2.2 trillion of damage to the global environment each year.
If serious environmental damaged was outlawed, she said, this money would flow into innovation.
She argued international legislation was the only way to fight ecocide because at present offending companies could deregister and register again in another territory.
Asked after her speech if her proposals were too radical to gain traction, Higgins said: "Something is always radical when it is innovative. The origin of the word radical means to pull out from the roots. I'm not anti-profit, but this is what I'm suggesting to turn around this sinking ship very fast."
She has already had some success in advancing law which protected the rights of nature. After proposing this legislation to the United Nations in April 2010, it was adopted by the Bolivian Government and incorporated into domestic law.
Higgins said the idea that non-human nature had rights was also already ingrained in Buddhist culture - 750 million people worldwide - and there was a strong appetite for it in indigenous cultures, including Maori.
"It is the developed world that has the disconnect," she said.