Writing in The Guardian he explained that there is now ‘widespread acknowledgement of an international “common law” of the environment based on principles such as sustainability and inter-generational equity’.

There are now over 360 specialist environmental courts or tribunals in 42 countries. He cited one judge in the Amazon area who created an environmental night school for offenders and who makes community service directly relate to the offence, e.g. waste dumpers are obliged to work in a recycling plant.

Lord Carnwath has been part of a judicial taskforce on these matters since 2002. He and his colleagues felt disappointment that the main Rio congress’s “common vision” document failed to contain ‘a more explicit commitment to extending these principles of how people, through the courts, can help effect real change, worldwide’.