Supreme Court unanimously finds plan to build third runway at Heathrow Airport is lawful

The Supreme Court has overturned a unanimous decision of the Court of Appeal, in finding that the Airports National Policy Statement (the “ANPS”) and its accompanying environmental report are lawful.

The ANPS is the framework that governs the construction of a third runway at Heathrow Airport and under which an application by a developer would be considered. This policy was designated as such by the Secretary of State in June 2018.

The defendant in this case, the Secretary of State for Transport, did not appeal the Court of Appeal’s decision and made no submissions to the Supreme Court. Instead, an interested party, Heathrow Airport Ltd (“HAL”) was granted permission to appeal to the Supreme Court. HAL owns Heathrow airport.

The Supreme Court decision

The Court of Appeal had found that the ANPS was unlawful on the basis of the following grounds, which the Supreme Court considered and rejected in turn.

“Government policy” ground

Pursuant to section 5(7) and (8) of the Planning Act 2008 (the “PA 2008”), the Secretary of State was required to give an explanation of how the policy set out in the ANPS took account of Government policy relating to the mitigation of, and adaptation to, climate change. It was a linchpin of the environmental activists’ success at the Court of Appeal that that Court decided that “Government policy” included the commitment to implement the emissions reductions targets under the Paris Agreement. In particular, it was the Court of Appeal’s view that there was nothing to warrant limiting the phrase “Government policy” to mean only the legal requirements of the Climate Change Act 2008 (the “CCA 2008”), finding that the concept of policy was broader than legislation.

The Supreme Court disagreed with this analysis. It took a purposive approach, explaining that the purpose of the section 5(8) is to make sure that there is a degree of coherence between the policy set out in the ANPS and established Government policies. It was the Court’s view that for the provision to operate sensibly the phrase must be given a relatively narrow meaning so that the relevant policies can readily be identified. Otherwise, civil servants would be required to “trawl” through Hansard and press statements to see if anything had been said by a minister which might be characterised as “policy”. The Court found that it could not have been Parliament’s intention to create “a bear trap” for ministers by requiring them to take into account any ministerial statement which could as a matter of ordinary language be described as a statement of policy relating to the relevant field.

As such, the Supreme Court held that when the Secretary of State designated the ANPS, there was no established Government policy beyond that already encapsulated in the CCA 2008. This is because, at that time, the Government’s approach on how to adapt its domestic policies to contribute to the global goals of the Paris Agreement was still in a process of development.

Section 10 ground

Under section 10(2) and (3) of the PA 2008 the Secretary of State is required to designate national policy frameworks with the aim of contributing to the achievement of sustainable development. The Court of Appeal found that the Secretary of State breached this duty when promulgating the ANPS in that he failed to have proper regard to the Paris Agreement.

The Supreme Court found that reasoning unsustainable. It held that the evidence demonstrated that the Secretary of State took the Paris Agreement into account and, to the extent that the obligations under it were already covered by the measures in the CCA 2008, he gave weight to it. Putting it another way, the Secretary of State was required to consider the CCA 2008; beyond that he had discretion whether to take the Paris Agreement further into account. The test to be applied to determining whether the exercise of that discretion was lawful was whether his decision was so irrational that no rational decision-maker would make it (the “Wednesbury Test”). This test was not met in this case. The Supreme Court held that the view formed by the Secretary of State, that the international obligations of the UK under the Paris Agreement were sufficiently taken into account for the purposes of the designation of the ANPS by having regard to the obligations under the CCA 2008, was “plainly” rational. This was bolstered by: the Secretary of State’s assessment based on expert advice from the Climate Change Committee (the “CCC”), an independent body; the ANPS indicating that the up-to-date carbon targets under the CCA 2008 would be taken into account at the stage of considering whether developer consent should be granted; and section 6 of the PA 2008 provides scope for the Secretary of State to amend the ANPS should that be necessary.

On this basis the Supreme Court overturned the Court of Appeal’s reasoning.

Environmental report ground

The Court of Appeal had found that the Secretary of State had breached his duty under article 5 of the Strategic Environmental Assessment Directive 2001/42/EC on the assessment of the effects of certain plans and programmes on the environment (the “Directive”) to issue a suitable environmental report for the purposes of public consultation on the proposed ANPS, by failing to refer to the Paris Agreement.

The Supreme Court explained that an environmental report for the purposes of the Directive is required to provide a basis for informed public consultation on the plan. Whether the information included in an environmental report is adequate and appropriate is a matter of discretion for the Secretary of State and the exercise of that discretion is subject to the Wednesbury Test. The Court found that this test had not been met given that the Secretary of State decided to follow the advice of the CCC to the effect that the UK’s obligations under the Paris Agreement were sufficiently taken into account in the UK’s domestic obligations under the CCA 2008, which were referred to in the ANPS and the appraisal of sustainability. The Supreme Court found in favour of HAL on this ground.

Post-2050/Non-CO2 emissions ground

Section 10(2) and (3) of the PA 2008 obliged the Secretary of State in performing his function of designating the ANPS to do so with the objective of contributing to sustainable development and in so doing to have regard to the desirability of mitigating, and adapting to, climate change. The Court of Appeal found that the Secretary of State breached this duty when promulgating the ANPS for two reasons.

First, he failed to have proper regard to the desirability of mitigating climate change in the period after 2050. However, the Supreme Court found that the Paris Agreement was still being developed in June 2018, when the ANPS was being designated.

Second, he had failed to have proper regard to the desirability of mitigating climate change by restricting emissions of non-CO₂ impacts of aviation, in particular nitrous oxide. The Supreme Court dismissed this argument, stating that it was a matter of discretion for the Secretary of State. Further, that discretion had not been exercised irrationally because of six reasons:

1. His decision reflected the uncertainty over the climate change effects of non-CO₂ emissions and the absence of an agreed metric which could inform policy.
2. It was consistent with the advice which he had received from the CCC.
3. It was taken in the context of the Government’s inchoate response to the Paris Agreement.
4. The decision was taken in the context in which his department was developing as part of that response its Aviation Strategy, which would seek to address non-CO₂
5. The designation of the ANPS was only the first stage in a process by which permission could be given for the third runway scheme to proceed and the Secretary of State had powers at the developer consent stage to address those emissions.
6. It is clear from both the appraisal of sustainability and the ANPS itself that the applicant for developer consent would have to address the environmental rules and policies which were current when its application would be determined.

On this basis the Supreme Court found in favour of HAL on this ground as well.

Comment

The Court of Appeal’s decision could be regarded, in some ways, as conservative, given that it decided not to quash the ANPS. Instead, it declared that the ANPS in its present form was unlawful and could not have legal effect. This gave the Secretary of State the opportunity to reconsider the ANPS. Nonetheless, the Supreme Court’s decision could make it significantly easier for the Secretary of State to proceed with plans for a third runway at Heathrow. However, this case has not been without its political twists and turns. Notwithstanding the Supreme Court’s decision, at the time of writing this blog, it has been reported that the Prime Minister has refused to endorse proposals for a third runway at Heathrow. It remains to be seen what happens next.