Bristol Airport Action Network Co-Ordinating Committee (acting through Stephen Clarke) v Secretary of State for Levelling Up, Housing and Communities

In planning decisions, aviation emissions cannot be ignored, but their legal treatment depends on the division between local planning control and national climate policy. Local policies may encompass aircraft emissions without directly regulating them. A decision-maker may assess their significance by asking whether the proposal would materially affect the United Kingdom’s ability to meet statutory carbon budgets and the net-zero target.

The assumption that national regulatory regimes will operate effectively is not necessarily irrebuttable, but it must be read with the decision letter as a whole. Scientific uncertainty may justify declining to quantify non-CO₂ aviation effects, particularly where no agreed metric or policy exists and future policy review is secured. Functionally linked habitat may be protected by mitigation where replacement habitat prevents adverse effects before development occurs.

The claimant sought statutory review of a decision by a panel of inspectors allowing Bristol Airport Ltd’s appeal against North Somerset Council’s refusal of permission for airport expansion. The proposal would increase annual passenger capacity by approximately 20 per cent.

Permission was granted on six grounds. Five concerned climate-change effects, including the interpretation of local planning policies, national aviation policy, the Climate Change Act 2008, local carbon budgets, and non-CO₂ emissions. The sixth concerned replacement foraging habitat for horseshoe bats associated with a special area of conservation.

The central issues were whether the Panel had erred in law or given inadequate reasons in assessing those matters.

1. The claim was dismissed. None of the six grounds disclosed a material error of law.
2. Policies CS1 and CS23 were broad enough to encompass aviation emissions. The Panel was nevertheless entitled to decide that those emissions were addressed indirectly, by reference to whether they were likely materially to affect the Secretary of State’s ability to meet obligations under the Climate Change Act 2008. Its conclusion that the policies did not directly address aviation emissions was not a finding that they had no application.
3. The Panel correctly interpreted the Making Best Use of Existing Runways policy. Read as a whole, the policy treated aviation carbon as an important environmental element for national consideration, while leaving local environmental impacts to local planning judgment.
4. The Panel was entitled to treat the statutory carbon-budget system and national and international trading schemes as a national framework within the scope of paragraph 188 of the National Planning Policy Framework. The paragraph 188 assumption was not irrebuttable, but the Panel’s reasons, read as a whole, showed that it had considered the United Kingdom’s failure to meet earlier budgets and the shortcomings of the trading schemes.
5. The Panel lawfully gave no weight to local carbon budgets. They had no basis in law or planning policy, and the Panel was entitled to assess the proposal in the national context. The uncontradicted nature of expert evidence did not require it to be given weight.
6. The Panel was entitled not to apply the BEIS 1.9 multiplier for non-CO₂ emissions. There was substantial scientific uncertainty, no agreed metric, and no policy requiring its use. The precautionary principle added nothing where the rational decision was to leave the issue for future consideration. The environmental statement was not defective because it identified the uncertainty and explained the limits of current knowledge.
7. Replacement habitat for functionally linked land was properly treated as mitigation. The evidence established that it would be provided in advance and would avoid adverse effects on the integrity of the special area of conservation. The distinction between mitigation and compensation depended on whether the measure prevented harm, not simply on whether the affected land lay outside the designated site.
8. The Panel’s reasons were adequate when read fairly and in the round. Section 31(2A) of the Senior Courts Act 1981 therefore did not require consideration.

First-instance statutory review of the inspectors’ decision allowing Bristol Airport Ltd’s planning appeal. The claim was dismissed.