The Zero Carbon Bill the Government is introducing is, on the face of it, good law.

It reflects the gravity of the challenge by setting a mid-century goal for greenhouse gas emissions, consistent with what would be required globally to limit warming to 1.5 degrees Celsius.

And it sets up a mechanism for translating that goal into a series of quantified medium-term targets against which policymakers can be held accountable and which should provide the essential balance of certainty and flexibility that businesses and investors need.


Whether the legislation achieves its purpose will depend on whether the National Party