In Bristol Airport Action Network Co-ordinating Committee v Secretary of State for Levelling Up, Housing and Communities [2023] EWHC 171 (Admin), the High Court dismissed a challenge brought primarily on climate change grounds by various local environmental groups and residents to the grant of planning permission for the expansion of Bristol Airport.

Key points

  • Planning authorities are entitled to consider in a generalised way whether emissions from a proposed development would materially affect the UK’s ability to meet its carbon budgets and targets.
  • Local decision makers may assume that separate pollution control regimes will operate effectively in respect of the emissions from a proposed development.
  • Aviation carbon emissions are primarily to be considered at a national, rather than local, level in accordance with Government policy.


The first interested party, Bristol Airport Ltd (“BAL“), applied to North Somerset Council (“the Council“) for planning permission to increase its capacity by about 2 million passengers per year. The application was refused by the Council, but BAL’s appeal against that refusal was allowed, following an inquiry by a panel of planning inspectors (the “Panel“).

In relation to climate change issues, the claimant alleged that the Panel erred in:

  1. Its interpretation that the Council’s development plan policies did not directly address aviation emissions;
  2. Its interpretation of the national policy “Making Best – Use of Existing Runways” (“MBU”);
  3. Finding that it was required to “assume” that the Secretary of State (“SoS“) would comply with his duty under the Climate Change Act 2008 (“CCA“), as per paragraph 188 of the National Planning Policy Framework (“NPPF”);
  4. Failing to consider the impact on the local carbon budget for the Council; and
  5. Its conclusion that the impact of non-CO2 emissions could be excluded from the Environmental Impact Assessment (“EIA“) prepared by BAL and should not weigh in the balance against the proposed expansion.

In the alternative, the claimant submitted that the Panel failed to give adequate reasons.


Lane J dismissed each of the grounds raised by the claimant, including the reasons challenge. In large part, the case was about the key question underpinning the inquiry (to which there was no substantial dissent): whether emissions from the proposal would be so significant that they would materially affect the ability of the UK to meet its carbon budgets and the target of net zero by 2050.

Ground 1

In relation to Ground 1, the court noted the principle in Tesco Stores Ltd v Dundee CC [2012] UKSC 13, that planning policy statements are not to be construed as statutory or contractual provisions.

Although the relevant policies here were broad enough to encompass the issue of aviation emissions, they did not seek to articulate how the Council should address that issue as a planning authority. Aviation emissions, which can occur at any point during an aircraft’s journey to and from the airport, are clearly of a different character to other forms of emissions that can be reduced in the Council’s own area. The Panel was entitled to conclude that aviation emissions should be addressed “indirectly“, meaning they would only become relevant if they were likely to have a material impact on the SoS’ ability to meet his climate targets and budgets (which the Panel did not consider to be the case here). Aviation emissions were not, therefore, a material consideration against BAL.

Ground 2

The court found that the Panel considered carbon emissions from all sources, including aviation, in detail. Referring back to the key question, the court noted that planning authorities are entitled to make judgments of a generalised nature about the likelihood of a proposal harming the achievement of a national target. The MBU, read as a whole, also showed that the admitted increase in CO2 emissions was a matter for national, not local, decision-making.

Ground 3

The claimant’s main argument was that the Panel erred in law in treating the CCA and the various duties placed on the SoS under it as a “separate pollution control regime” that would operate effectively, relying on the different approach taken in relation to air quality in Gladman Developments Ltd v Secretary of State for Communities and Local Government and others [2019] EWCA Civ 1543.

Lane J explained that the relationships between local and national decision-making in the areas of air quality and emissions from aviation are significantly different, with the latter controlled at the national level pursuant to the CCA, including through trading schemes by contrast to air quality issues which have a significant and discrete local element. Disapplying the assumption in paragraph 188 of the NPPF, that other regimes would operate effectively, would lead local decision makers into an area of national policy with which they are not directly concerned.

Ground 4

The court found that the impact of the proposal on the Council’s local carbon budget was only a consideration “to which the decision-maker may have regard if, in their judgment and discretion, they think it is right to do”, (the third category of ‘relevant considerations’ summarised in R (Friends of the Earth Limited) v Heathrow Airport Limited [2020] UKSC 52 (“Friends of the Earth“).

Given the decision letter demonstrated that the Panel engaged with the issue before concluding that it had no basis in law or policy, and therefore giving it no weight, the claimant failed to overcome the high threshold of irrationality. Lane J reiterated the court’s concern not to adopt a stance which may result in it wrongly substituting its own view on weight for that of the decision-maker.

Ground 5

The claimant submitted that the impact of non-CO2 emissions was a matter of critical importance to determining the impact of the airport’s expansion on climate change and should have been in the environmental statement.

Lane J referred to the “well-established” position that EIA compliance is a matter of planning judgment, challengeable only on a Wednesbury basis. The EIA did not ignore the non-CO2 emissions but noted the uncertain state of scientific knowledge regarding their assessment, and their present exclusion from domestic and international legislation and targets. Accordingly, the EIA did not disclose a ‘patent defect’ that the Panel unlawfully failed to recognise. Applying Friends of the Earth, leaving a matter about which there is scientific uncertainty for further consideration within the development process did not breach the precautionary principle.


This judgment, which began by acknowledging the “very great importance” of climate change and the international consensus on the need to reduce CO2 emissions, is the latest in a growing line of climate change challenges. In a decision that will be welcomed by the aviation industry, the court afforded a wide margin of discretion to the Panel’s assessment of the impact of the proposed expansion on the ability of the UK to meet its carbon budgets, and reiterated its very limited role as regards to the application of policy and weight to be given to various factors.

The judgment also contains useful guidance on evaluating emissions in EIAs, particularly in respect of non-CO2 emissions. In light of significant scientific uncertainty, it was open to BAL to leave the issues to be dealt with when the science allowed. Scientific developments in this area could shift the dial on the need to address non-CO2 emissions.

Andrew Lidbetter
Andrew Lidbetter
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Nusrat Zar
Nusrat Zar
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Jasveer Randhawa
Jasveer Randhawa
Professional Support Consultant
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Katie-Scarlett Wetherall
Katie-Scarlett Wetherall
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