A climate change lawsuit making its way through the courts continues to prove one of New Zealand’s most historic legal cases.

The case, brought by iwi leader and climate activist Mike Smith, seeks to hold several major companies, including Fonterra and Z Energy, legally responsible for their greenhouse gas emissions.

It has already prompted the government to reform New Zealand’s climate laws to prevent companies being sued for damages caused to the climate by their emissions.

Having just been introduced under urgency to parliament, where it passed its first reading yesterday, the Climate Change Response (Tort Liability) Amendment Bill would apply to both current and future cases if enacted.

The government’s reasoning is that climate policy should be decided by elected officials and existing laws, not by the courts, to ensure “legal clarity and certainty” for businesses around their obligations.

Now the dispute has taken another turn. Smith has filed fresh proceedings in the High Court, asking for a declaration that the government’s decision to introduce the law change – and the process behind it – were unlawful.

There are many interesting aspects of these cases that legal observers will be following closely. Among them is whether New Zealand’s proposed law........

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