The Court of Appeal of England and Wales ruled that the UK Government’s proposed expansion of Europe’s busiest airport – and the busiest in the world with two runways – was “unlawful” because it did not take international climate change commitments into account.

Heathrow Airports Ltd said it would challenge the decision, but the UK Government has not sought permission to appeal to the UK Supreme Court.

The appeal judges said that a third runway could still go ahead, as long as it fits with the UK’s climate policy.

‘Third runway’

The action brought by Friends of the Earth and other environmental groups, as well as a number of London councils and the Mayor of London, concerned the proposed expansion of capacity at Heathrow Airport by the addition of a third runway under the policy set out in the Airports National Policy Statement: new runway capacity and infrastructure at airports in the south east of England’ (ANPS). 

That document, designated by the then Secretary of State for Transport in June 2018, is a national policy statement prepared under section 5(1) of the Planning Act 2008.

It was subject to a number of legal challenges brought by claims for judicial review, which were dismissed by the Divisional Court, following which appeal judges Lord Justice Lindblom, Lord Justice Singh and Lord Justice Haddon-Cave were asked to consider whether the lower court was wrong to conclude that the Government’s policy in favour of the development of a third runway at Heathrow was produced lawfully.

The main issues for the court to decide were: first, issues on the operation of EC Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora (“the Habitats Directive”); second, issues on the operation of EC Council Directive 2001/42/EC on the assessment of the effect of certain plans and programmes on the environment (“the SEA Directive”); and third, issues relating to the United Kingdom’s commitments on climate change as set out in the Paris Agreement.

‘Legally fatal’

Allowing the appeal, the judges held that the ANPS was “unlawful” because it failed to take into account the Paris Agreement, and that “appropriate form of relief” was to prevent the ANPS from having any legal effect unless and until the Secretary of State has undertaken a review of it.

The judgment of the court stated: “Like the Divisional Court, we have concluded that the challenges to the ANPS must fail on the issues relating to the operation of the Habitats Directive, and also on all but one of the issues concerning the operation of the SEA Directive. However, for the reasons we have given, we have concluded that in one important respect the ANPS was not produced as the law requires, and indeed as Parliament has expressly provided.

“The statutory regime for the formulation of government policy in a national policy statement, which Parliament put in place in the Planning Act, was not fully complied with. The Paris Agreement ought to have been taken into account by the Secretary of State in the preparation of the ANPS, but was not. What this means, in effect, is that the Government when it published the ANPS had not taken into account its own firm policy commitments on climate change under the Paris Agreement.

“That, in our view, is legally fatal to the ANPS in its present form. As we have explained, the normal result in a successful claim for judicial review must follow, which is that the court will not permit unlawful action by a public body to stand. Appropriate relief must therefore be granted. We have formulated a declaration that is, in our view, appropriate, necessary and proportionate in the light of our conclusions as a whole. A declaration has binding effect.

“We have not decided, and could not decide, that there will be no third runway at Heathrow. We have not found that a national policy statement supporting this project is necessarily incompatible with the United Kingdom’s commitment to reducing carbon emissions and mitigating climate change under the Paris Agreement, or with any other policy the Government may adopt or international obligation it may undertake.

“That is not the outcome here. However, the consequence of our decision is that the Government will now have the opportunity to reconsider the ANPS in accordance with the clear statutory requirements that Parliament has imposed.”