UK: The Court of Appeal and the Third Runway: how the enforcement of climate change commitments grounded Heathrow’s plans for expansion

The Court of Appeal (Court) judgment deals with three appeals from the Divisional Court, brought by local authorities, environmental organisations and the Mayor of London. The three issues before the Court were:

The Court upheld the Divisional Court's ruling in relation to the first and second issues, but crucially overturned the decision in relation to the third issue.

How did we get here?

Airports National Policy Statement (ANPS), which supported the proposed expansion of capacity at Heathrow Airport through an additional third runway. Section 5(8) of the Planning Act 2008 requires these types of policy statements to “include an explanation of how the policy set out in the statement takes account of Government policy relating to the mitigation of, and adaptation to, climate change”.

The issue before the Court was therefore whether the Government’s commitment to the Paris Agreement (the “Agreement”) constituted “Government policy” on climate change, and consequently required the Secretary of State to take it into account.

The Agreement is as international treaty falling within the United Nations Framework Convention on Climate Change. The Agreement is a commitment by 189 countries, including the United Kingdom, aimed at addressing the threat of climate change by keeping a global temperature rise well below 2ºC and pursuing efforts to limit it to 1.5ºC. The parties have a binding commitment to implement domestic measures to achieve their nationally determined emissions targets.

In addition, the UK is also subject to a legally binding commitment to reduce greenhouse gas emissions under the Climate Change Act 2008 (the “CCA”). The CCA initially set a target to reduce carbon emissions by 80% by 2050, but that figure was amended to “net-zero” following a recommendation by the Committee on Climate Change (“CCC”), the UK’s independent climate advisory body, in 2019. It was submitted by the Secretary of State that the CCA targets do not include emissions from international aviation – such carbon emissions to be no more than 2005 levels in 2050. The Secretary of State argued instead that “those [section 10(2) and (3) of the Planning Act] provisions provide a very strong pointer that such matters [international commitments] should not be considered: the clear intention of Parliament being that consideration should be given only to existing domestic legal obligations and policy commitments in relation to the mitigation of, and adaptation to, climate change” (paragraph 218).

This argument was rejected by the Court. For the Secretary of State to rely on this carve out in the legislation, it would frustrate the overriding purpose of “Government policy”, which the Court stated was “necessarily broader than legislation” (paragraph 224). In making their decision, the Court made reference to exchanges between the Secretary of State and the CCC, whereby the Secretary of State expressed a clear commitment to adhering to the Agreement.

Based on the fact that the UK ratified the Agreement in November 2016 and that various Ministers made statements re-iterating adherence to the Agreement, the Court held that it was clearly part of“Government policy”>. Despite this, the Secretary of State did not take the Agreement into account when drafting the ANPS. The Court therefore found that section 5(8) of the Planning Act 2008 had not been complied with.

The Court considered the lack of consideration for the Agreement by the Secretary of State “legally fatal to the ANPS in its present form” and therefore ruled the ANPS unlawful in its current form. While the expansion project is not inherently illegal, if it is to go ahead, the Government will need to comply with these statutory requirements obliging meaningful consideration of the third runway’s climate change implications.

The Court reiterated that, while the Planning Act does require the Agreement to be taken into account, including providing an explanation of how this has been done, it does not require the Secretary of State to act in accordance with or conform to the policy contained in the Agreement.

What happens now?

Heathrow Airport Ltd, an interested party to the proceedings, has expressed its intention to appeal the decision to the Supreme Court and has also stated publicly that the issue identified by the Court is “eminently fixable”. It may seek to prove compatibility with the UK’s climate change commitments and justify the expansion through technological advancements and carbon off-setting. At present, the Government has not asked to appeal the decision and has indicated that any appeal should be industry led. The Government must now reassess the ANPS in accordance with the clear statutory requirements, and either amend the ANPS to comply with the UK's commitments, or abandon the project altogether.

Growing importance of climate change commitments

The judiciary were clear in stating that “[t]he issue of climate change is a matter of profound national and international importance of great concern to the public – and, indeed, to the Government of the United Kingdom and many other national governments" (paragraph 277). The UK judiciary has shown a willingness to hold the Government accountable to its climate change policy, even where this might be at odds with economic policy and industry interests. This accountability will surely, the authors contend, shape public policy moving forward and see a new level of scrutiny placed on governments, developers and public authorities, who must now take climate change commitments into more careful consideration. Compliance with environmental regulations cannot be considered a background issue. At a minimum, further rulings on the Agreement internationally and similar challenges to carbon-intensive infrastructure projects are expected.

If you want to know more about how this ruling, the Agreement or how any other ESG legislation may affect your business, please don’t hesitate to contact one of our industry specialists who would be delighted to chat through any queries you may have.