Peter Barclay & Anor v Secretary of State for Transport

In determining an application for development consent where no national policy statement has effect, the Secretary of State must apply the statutory framework in section 105 of the Planning Act 2008 and have regard to matters considered important and relevant. A national policy statement may remain an important and relevant consideration even if it does not apply directly and has become subject to later developments.

Environmental impact assessment significance and planning-policy acceptability are distinct questions. A project may have significant adverse effects without materially affecting national carbon targets. The decision-maker may use a qualitative assessment where no reliable quantitative methodology or benchmark exists. The weight given to significant effects remains a matter for planning judgment, provided the decision-maker reaches a reasoned conclusion and integrates it into the decision.

Two rolled-up judicial review claims challenged the Secretary of State’s decision of 21 September 2025 to grant development consent for the Gatwick Airport Northern Runway Project Development Consent Order 2025. The project would enable dual-runway operations and associated airport, surface-access and infrastructure works.

The challenges concerned interpretation of the Airports National Policy Statement and aviation policy; the statutory relationship between the Planning Act 2008 and the Climate Change Act 2008; greenhouse-gas emissions, including inbound international and non-CO₂ emissions; delivery risks under the Jet Zero Strategy; noise; economic benefits; cumulative effects; and wastewater-treatment requirements.

1. Disposition. Permission was granted on grounds (1) and (4) of Mr Barclay’s claim and on grounds (1), (6) and (7) of CAGNE’s claim. Those grounds were rejected. Permission was refused on the remaining grounds. Both claims were dismissed.
2. Policy framework. The Airports National Policy Statement did not have effect for the Gatwick application, but remained an important and relevant consideration under section 105(2)(c) of the Planning Act 2008. Properly construed with the Aviation Policy Framework and Making Best Use policy, it supported making best use of existing runways at airports beyond Heathrow, including Gatwick. The proposed development nevertheless had to demonstrate a need additional to or different from that met by the Heathrow Northwest Runway scheme.
3. Climate change and EIA. The Secretary of State was entitled to distinguish the EIA question whether effects were significant from the policy question whether emissions were sufficiently material to justify refusal. A project could fall short of fully contributing to the net-zero trajectory and therefore produce significant adverse effects, while remaining below the threshold in paragraph 5.82 of the Airports National Policy Statement. The conclusions were not contradictory.
4. Following R (Finch) v Surrey County Council, downstream emissions from inbound international flights were effects requiring consideration. However, the Secretary of State could conclude that they could not be assessed meaningfully on a quantitative basis in the absence of an appropriate benchmark. A qualitative assessment was lawful.
5. The Secretary of State was entitled to adopt a qualitative assessment of non-CO₂ emissions because no established methodology or scientific consensus existed for quantifying their significance in a planning decision. The precautionary principle did not require an unreliable quantitative estimate.
6. Delivery risks concerning the Jet Zero Strategy were matters for the statutory climate-change framework and the Secretary of State responsible for section 13 of the Climate Change Act 2008. The decision-maker determining an individual development-consent application could rely on extant government policy and need not undertake an economy-wide review of delivery risk.
7. The decision-maker was entitled to give neutral weight to residual significant noise effects where the project complied with applicable noise policy and the balance of impacts and benefits justified that evaluation. Neutral weight was not necessarily no weight.
8. The Secretary of State was entitled to conclude that the wastewater requirement ensured sufficient treatment capacity would exist before dual-runway operations began. The provision did not irrationally require the treatment works to be operational before those operations, and its tailpiece provided limited flexibility to agree alternative means of achieving the requirement’s purpose.

First-instance judicial review claims. The judgment does not state any appeal from an earlier decision in the same litigation.