On June 23, 2026, the High Court handed down its judgment in Barclay and CAGNE v SST and Gatwick Airport (interested party)  [2026] EWHC 1556 (Admin). The judgment followed a four-day hearing from January 20-23, 2026. Both Claimants had sought permission to bring a claim for judicial review of the Secretary of State for Transport's decision of September 21, 2025, to make the Gatwick Airport (Northern Runway Project) Development Consent Order 2025 (the "DCO"). The DCO authorises development which will enable dual runway operations at Gatwick Airport.

Mr Barclay advanced five grounds of challenge: 
(1) The SST failed properly to understand the Airports National Policy Statement (June 2018) [“the ANPS”] and/or failed to have regard to the relevant policy of the ANPS concerning the expansion of Gatwick Airport. (2) In granting development consent pursuant to section 114 of the 2008 Act, the SST was obliged but failed to exercise her power so as to promote the policies and objects of the statutory scheme. (3) In making the DCO the SST acted in breach of certain provisions of the Infrastructure Planning (Environmental Impact Assessment) Regulations 2017 [“the EIA Regulations”] and/or failed to reach conclusions on the DCO and/or the adequacy of the environmental impact assessment [“EIA”] for the proposed development in a procedurally rational manner; or alternatively, the SST’s conclusions were Wednesbury unreasonable. (4) The SST’s consideration of need and economic benefits was procedurally irrational and/or Wednesbury unreasonable. (5) The SST erred in her interpretation of the Aviation Policy Framework (March 2013) [“the APF”] and ANPS policies governing aviation noise and/or in any event, reached irrational conclusions on noise.

CAGNE advanced six grounds of challenge: 
(1) The SST took an irrational approach to the significance of GHG emissions and/or failed to give adequate reasons for her approach to that issue. (2) The SST erred in law in her consideration of GHG emissions from international inbound flights under the EIA Regulations. (3) The SST erred in law in her consideration of non-carbon dioxide (CO2) emissions under the EIA Regulations. (4) The SST failed to take into account material risks to the Jet Zero Strategy (July 2022) [“JZS”] and/or to comply with her Tameside duty of reasonable inquiry and/or took an irrational approach to the JZS. (5) The SST unlawfully failed to weigh harmful noise impacts in the planning balance. (6) The SST imposed an unlawful requirement in Schedule 2 to the DCO in respect of Work No 44 (wastewater treatment works). 

Paragraph 366 of the judgment records the outcome:  "I grant permission on grounds (1) and (4) of Mr Barclay’s claim but reject both grounds. I refuse permission on grounds (2), (3) and (5) of Mr Barclay’s claim. I grant permission on grounds (1), (6) and (7) of CAGNE’s claim but reject each of those grounds. I refuse permission on CAGNE’s grounds (2), (3) and (4). CAGNE withdrew ground (5) of its claim. The overall outcome is that both claims are dismissed."

CAGNE and Mr Barclay applied for permission to appeal the High Court judgment. But on August 4, 2026, the Court refused their application. The Court of Appeal held that: (1) the SST had correctly interpreted the ANPS; (2) on the evidence, the High Court judge had reached accurate factual conclusion in the assessment of economic benefits; (3) the question under the ANPS of whether the development's failure to contribute to net zero was "so significant that it would have a material impact on the government's ability to meet its carbon reduction targets ... involved a question of degree which was a matter of judgement for the SST"; (4) the SST's decision to rely on a qualitative (rather than quantitative) assessment of the impact of non-CO2 emissions from the development had not been "irrational"; (5) the SST's approach to information relating to the government's Jet Zero strategy for reducing aviation emissions had not been irrational; and (6) the risks regarding the capacity to manage waste water did not require more than what the SST had already required when making the DCO.

Barclay and Communities Against Gatwick Noise Emissions (CAGNE) v Secretary of State for Transport

<p>This entry was provided by the Sabin Center for Climate Change Law. Please see the terms of use for citation and licensing of third party data.</p>

Barclay and Communities Against Gatwick Noise Emissions (CAGNE) v Secretary of State for Transport - decision

Filed

The Climate Litigation Database

Find climate change litigation data and indicators for {text}.

{text} litigation

Sabin Center for Climate Change Law provides Climate Litigation Database, a comprehensive database of US and Global climate change caselaw

Quickly and easily search through the complete text of thousands of climate change law and policy documents from every country.

Search the Climate Litigation Database

An aim to achieve a quantifiable outcome within a given time-frame, set by an institution such as a national government.

Policy instruments are techniques or tools used by governing authorities to promote certain policies in order to achieve predetermined goals. Put simply, instruments are how a government tries to achieve its goals, with this taxonomy being focused on national policy instruments.

Risk is the potential for adverse consequences resulting from the dynamic interplay between (climate-related) hazards, exposure, and vulnerability of affected human or ecological systems.

Groups  of people who are adversely affected by climate change or the response to it

A set of principles, processes, and practices that build economic and political power to shift from an extractive economy to a regenerative economy.

Justice is the ethical and political framework that addresses fairness, including issues of responsibility, rights, and structural inequity.

Renewable energy means all forms of energy produced from renewable sources in a sustainable manner.

Fossil fuel is a generic term for non-renewable energy sources such as coal, fossil gas, and oil (including crude oil, and petroleum products), that can be used for electricity and heat generation. Fossil fuels are hydrocarbons formed from pressurised and heated organic material buried over millions of years.

Molecules in the atmosphere that play a key role in the greenhouse effect by trapping heat radiating from Earth’s surface.

Area of the economy in which actors engage in identical or related activities.

In human systems, the process of adjustment to actual or expected climate change and its effects, in order to moderate harm, increase resilience or exploit beneficial opportunities. In natural systems, the process of adjustment to actual climate change and its effects; human intervention may facilitate adjustment to expected climate change and its effects.

The management and allocation of funds, assets and investments to meet various objectives

Tradable permits are market-based tools that grant permission for specific activities, frequently used to regulate emissions. These permits can be issued within a trading system to manage environmental impacts.

A target to reduce the prevalence of a greenhouse gas over a specific time frame

A commitment to balance GHG emissions with removal by a certain point in time, effectively reducing the net emissions to zero

Either money or something of monetary value is transferred between two or more organisations, people or countries.

Conditions that enhance the feasibility of adaptation options. Enabling conditions include finance, technological innovation, strengthening policy instruments, institutional capacity, multi-level governance and changes in human behaviour and lifestyles.

Actions or measures to adapt freshwater systems to climate change.

Actions to adapt human health, healthcare systems and well-being to climate change.

Actions or measures to adapt freshwater, coastal and marine systems to climate change.

A long-lived, colourless gas, chiefly emitted from fossil fuel combustion, deforestation and cement production.

Actions to reduce emissions in energy generation and supply.

Energy derived from biological compounds that are renewable due to their short life cycle within the carbon dioxide cycle.

This sector involves managing waste treatment, sanitation, pollution control and environmental cleanup.

Activities that involve planning, designing and building infrastructure, residential, and commercial structures.

This sector involves activities to move goods and people, alongside the storage of products.

This sector involves activities that impart knowledge and skills to individuals, including formal schooling, vocational training and educational support.

Activities of government agencies and institutions that provide public services, enforce laws and manage public resources.

This sector involves the distribution, treatment, and conservation of water resources.

Slow onset events evolve gradually from incremental changes over many years or from increased frequency or intensity of recurring events. As defined in the Cancun Adaptation Framework (2010), slow onset events include risks and impacts from rising temperatures, desertification, biodiversity loss, land and forest degradation, glacial retreat, ocean acidification, sea level rise, and salinization.

Barclay and Communities Against Gatwick Noise Emissions (CAGNE) v Secretary of State for Transport - decision

Target

Policy instrument

Risk

Renewable energy

Greenhouse gas

Economic sector

Adaptation/resilience

Finance