Supreme Court set to hear Smith v Attorney-General next week
Climate will be back in the Supreme Court next week, as it hears Mr Smith’s appeal in Smith v Attorney-General (which is a separate case from Smith v Fonterra, Mr Smith’s proceeding against New Zealand’s six largest corporate emitters).
In this case, Mike Smith (Ngāpuhi and Ngāti Kahu) claims that the Crown’s response to climate change has been, and is, inadequate to mitigate the risk that climate change presents, especially for Māori. Mr Smith pleads that climate change will harm whenua to which he and his whānau have a connection, and will, at a wider level, harm Māori disproportionately. This is due to the effect of both the Crown’s own emissions and also the effect of its response to the rest of the country’s emissions.
There are three arguments that Mr Smith is pursuing at the Supreme Court. He is arguing that the Crown’s response to climate change has been inadequate, and, as such has breached the following:
A public law duty to protect him and his descendants from the adverse effects of climate change;*
His and his descendants’ rights to life and culture affirmed in the New Zealand Bill of Rights Act 1990 (NZBORA); and
The Treaty of Waitangi.
Te Hunga Rōia Māori o Aotearoa | The Māori Law Society and Te Kāhui Tika Tangata | Human Rights Commission will both be appearing in the Supreme Court as interveners, assisting the Court on legal issues within their expertise; here, the Court will have the benefit of specialist submissions on tikanga and te Tiriti, and on the human rights dimensions of the Crown's climate response.
The hearing is from Monday 17 to Wednesday 19 August next week. The hearing is open to the public (in Courtroom 11 at the Auckland High Court) and will also be live-streamed on the Courts of New Zealand website.
What’s happened so far: Strike-out applications
The Attorney-General applied to strike out Mr Smith’s claims before it would proceed to a full trial. The threshold for a strike-out is whether the arguments being made by Mr Smith are “so clearly untenable that they cannot succeed”.
The High Court delivered its judgment on the strike-out application on 15 July 2022, finding that Mr Smith’s claims were untenable and struck out the proceedings.
Mr Smith appealed. On 19 December 2024, the Court of Appeal dismissed Mr Smith’s appeal, holding that the claims, as pleaded, were untenable. As we discussed at the time, the Court of Appeal’s judgment was far from a closed door on rights-based climate claims, expressly leaving the door open for future claims.
Most significantly, the Court concluded that it was “not clearly untenable” that an inadequate response by the Crown to the risks from climate change could give rise to a breach of the right to life (s 8, NZBORA), and the right to culture (s 20, NZBORA). On the right to life, the Court said (at [88]):
“Given the context of the climate emergency, which can be described as one of the greatest human rights challenges the world has ever seen, and the developing jurisprudence around the world responding to this challenge, we consider that an art 2-consistent interpretation of s 8 that a right to life encompasses a requirement to take protective measures against foreseeable threats to life is not so clearly untenable that it cannot succeed...”
(Footnotes omitted)
In other words, the Court accepted that climate change is properly understood as a human rights issue, and that ss 8 and 20 might impose positive obligations on the Crown, including as “international jurisprudence on these comparable rights recognises that a state’s response to climate change may engage these rights”. However, the hurdle was how the case was pleaded.
The Court was also clear that “rapid and deep reductions in greenhouse gas emissions are necessary, with the window of opportunity to ensure a liveable and sustainable future for all rapidly closing” (at [13]) - and that as the window for action closes, “the reasonableness of decisions made will require closer scrutiny”.
What to watch for
The wider legal landscape has changed significantly since the Court of Appeal delivered its judgment in December 2024. There are a couple of particular points that are likely to be at issue in the hearing:
Significant international law developments
A particularly notable area of change has been international law. This is especially so given the weight the Court of Appeal placed on international jurisprudence when interpreting NZBORA in the climate context, particularly in its interpretation of what the right not to be deprived of life constitutes in the context of climate change.
The most significant change in international law is the release of the International Court of Justice’s Advisory Opinion of July 2025 on the Obligations of States in respect of Climate Change, which clarified States' obligations under international law. Among other things, the International Court of Justice found that:
“[t]he environment is the foundation for human life, upon which the health and well-being of both present and future generations depend” and “the protection of the environment is a precondition for the enjoyment of human rights”, and that the “degradation of the climate system and of other parts of the environment impairs the enjoyment of a range of rights protected by human rights law” (at [373]-[375]);
The Court specifically addressed the adverse effects of climate change and how it may impair the enjoyment of the right to life in various ways, and that “the human right to a clean, healthy and sustainable environment is essential for the enjoyment of other human rights” (at [393]);
“Taking into account the adverse effects of climate change on the enjoyment of human rights, the Court considers that the full enjoyment of human rights cannot be ensured without the protection of the climate system and other parts of the environment. In order to guarantee the effective enjoyment of human rights, States must take measures to protect the climate system and other parts of the environment. These measures may include, inter alia, taking mitigation and adaptation measures, with due account given to the protection of human rights, the adoption of standards and legislation, and the regulation of the activities of private actors. Under international human rights law, States are required to take necessary measures in this regard” (at [403]).
Domestic law has also shifted (backwards)
Another point of interest will be how the recent and proposed amendments to the Climate Change Response Act 2002 (CCRA) are dealt with, including the Tort Prohibition Bill (targeting Mr Smith’s separate tort claim in Smith v Fonterra).
For example, at [95] of the Court of Appeal’s judgment, reference is made to an argument put forward by Mr Smith where it is “alleged that the 2050 net zero target is not within the range of reasonable targets having regard to the best available science”, particularly “because it does not include biogenic methane which has its own separate (lesser) targets”.
The aforementioned 2050 biogenic methane target has, of course, been weakened since the Court of Appeal’s decision: in December 2025, under urgency and without select committee scrutiny, Parliament passed the Climate Change Response (2050 Target and Other Matters) Amendment Bill, cutting the 2050 biogenic methane target from a 24 - 47% reduction below 2017 levels to just 14 - 24%. In the Government's own commissioned review, only the very top of the new range (24%) is consistent with 1.5°C-aligned pathways, with the bottom of the range corresponding to a world heading toward 2.7°C. The Supreme Court will be considering whether there is a tenable argument that the Crown’s climate response breaches fundamental rights (amongst other arguments) at the very moment New Zealand’s climate framework law has been, and continues to be weakened.
Cases like this one arise because political processes have not kept pace with the scale of the risk of climate change. In New Zealand, it is arguable that political processes to address climate change have stalled or even begun to run backwards. However, New Zealand has a well-established legislative framework for protecting human rights, and there is a legitimate question as to whether the Crown’s actions (or inaction) on climate change breach those rights. Mr Smith and his legal team have spent more than six years carrying these questions through the courts on behalf of his whānau, his iwi, and future generations.
Footnotes:
*In the lower courts, this was framed as a common law duty; however, based on the Supreme Court’s case synopsis released on 31 July 2026, this has been reframed as a public law duty. Mr Smith also claimed a breach of fiduciary or fiduciary-like duties in the lower Courts, but this is no longer being pursued in the Supreme Court.