Supreme Court hears Horse Hill case

The legal case brought by campaigner Sarah Finch on behalf of the Weald Action Group, over the Horse Hill oil site was heard by five judges in the Supreme Court on 21 and 22 June.

The court case challenges the decision by Surrey County Council to grant planning permission to Horse Hill Developments Ltd (controlled by UK Oil & Gas PLC [UKOG]) for four new oil wells and 20 years of oil production. Sarah argues that this decision was not lawful as the Council had failed to assess the full climate impact of the scheme.

The Supreme Court hearing was the culmination of a three-year legal fight. Sarah’s arguments were rejected by the High Court in December 2020, and by the Court of Appeal in February 2022, though, very unusually, the Court of Appeal’s judgment was split: two of the judges found that the Council had acted lawfully, but the third agreed with Sarah that it had not.

As the case highlighted a glaring gap between planning practice and the UK’s climate policies – and as the Court of Appeal’s judgment showed that even senior judges don’t agree on how to interpret the law on this matter – Sarah appealed to the Supreme Court. They agreed to hear the case.

The Supreme Court only hears cases of the greatest public or constitutional importance affecting the whole population. This is one of the first climate cases to go before it. It was also the first time the Office of Environmental Protection, established in 2021 as an independent watchdog for enforcing environmental law, has intervened in a court case. So the hearing was a big deal for everybody involved and for environmental and climate law in the UK.

Respondents and intervenors

Several parties had joined the case as ‘respondents’ or ‘intervenors’ – giving them the right to submit their views, either in the courtroom or in writing. Horse Hill Developments Ltd and the Minister for Levelling Up, Housing and the Communities were ‘respondents’ (on the Council’s side) and Friends of the Earth joined as an ‘intervenor’ (on Sarah’s side) from the beginning. Three more parties got involved at the Supreme Court stage: Greenpeace , the Office for Environmental Protection, and West Cumbria Mining Ltd (the company behind Britain’s first new coal mine for decades).

Climate impacts of use of the oil ignored

The key question the Court was asked to clarify was whether it was lawful for the Council to allow the greenhouse gas emissions resulting from the eventual use of the oil – called ‘downstream’ emissions – to be excluded from the environmental impact assessment (EIA) of the proposed development.

The proposal was for production of up to 3.3 million tonnes of crude oil. All the parties agreed that it was inevitable that this oil would ultimately be burned, causing greenhouse gas emissions, and that these emissions would have a significant harmful impact on the climate.

The Council had initially recommended that the EIA should cover “the global warming potential of the oil and gas that would be produced”. However after correspondence with HHDL, they decided it need only cover the greenhouse gases produced during the production process on-site. The latter were estimated at 112,000 tonnes of CO₂ equivalent, a tiny fraction of the estimated more than 10 million tonnes which would be produced when the oil was burned.

Key issue 1: What is an ‘indirect impact’?

Under the Town and Country Planning (Environmental Impact Assessment) Regulations 2017, developers of a project that meets the criteria for EIA must assess all the “likely significant effects of the proposed development”. Government guidance says that these should cover “the direct effects and any indirect, secondary, cumulative, short, medium and long term, permanent and temporary, positive and negative effects of the development”.

Sarah’s lawyers argued that the carbon emissions from use of the oil to be produced at Horse Hill were “indirect effects” of the proposed operation. Lawyers for the respondents all argued that they were not “effects of the development” – which they limited to the operations on the site. They said that as the oil would be refined and sold before it could be used, and the emissions would happen in a time and place outside HHDL’s control, they were too distant from the project to be considered an indirect effect of it.

Harriet Townsend, representing Surrey County Council, said: “Although combustion is inevitable, the project would be complete without combustion… The project is only the extraction of oil.” Richard Moules, representing the Minister for Levelling Up, Housing and the Communities, said, “The indirect effects have to be intrinsic to the construction or operation of the project.”

One of the judges, Lord Leggatt, commented, “It sounds like a piece of medieval sophistry to me… You extract the oil and then you sort of blank out what’s going to happen to it afterwards.”

Estelle Dehon KC, representing Sarah, argued that the fact that there would be intervening processes before the oil was burned was what made this an indirect, rather than a direct, effect. She said: “One cannot use those intervening steps as a way to define the indirect effects out of being one. Because the whole point of an ‘indirect’ effect is that there are these intervening steps.”

Key issue 2: is EIA a matter for planners’ judgment or a matter of law

In the Court of Appeal, Sir Keith Lindblom had ruled that “the question of whether a particular impact on the environment is truly a “likely significant [effect]” of the proposed development – be it a ‘direct’ or ‘indirect’ effect – is ultimately a matter of fact and evaluative judgment for the [planning] authority”. Sarah’s lawyers argued that it was not a matter of judgment but of law.

The Office for Environmental Protection, in its written submission, said the Court of Appeal’s judgment: “is likely in practice to give rise to the risk of inconsistent decisions between local planning authorities and other relevant decision-makers under the EIA regime on matters which are likely to be of significant importance and controversy, and where a common and consistent approach would be desirable.

“The Court of Appeal decision seems likely to result in repeated litigation on the same point. The OEP submits that the meaning of the words used in the legislation, including the words ‘indirect effects’, should be a matter of law, and not simply of planning judgment.” We agree.

“The public will wonder why this is not already happening”

Summing up, Sarah’s advocate Estelle Dehon KC said, “To conclude, the appellant submits there is no natural or rational impediment to the assessing the downstream emissions of fossil fuel development. The public will wonder why this is not already happening, given that the point of fossil fuel production is for it to be burned and in light of the climate crisis that we face. 

“This court can clarify the position and ensure that EIA is applied in a consistent way in finding downstream greenhouse emissions are, as a matter of law, indirect effects of fossil fuel development that falls within EIA and/or, according to whether the court sees fit according to the OEP’s submissions, to make appropriate further guidance.”

Wider impacts 

If the Supreme Court decides in Sarah’s favour, planning authorities across the UK will be obliged to consider emissions from the eventual use of fossil fuels when deciding on planning applications for their production. This would make it much more difficult for future developments to get planning permission, and will also support the review of already permitted projects. Developments that could be affected include the proposed coal mine in Cumbria, which was approved by the Government but is subject to challenge by campaigners, and Rosebank, the biggest undeveloped oil field in the North Sea, which could get Government approval imminently.

Next steps

There’s now a long wait till we get the judgment. It can take three to six months – or longer – for the judges to reach a conclusion. We will report developments here.

Sarah was represented by Leigh Day solicitors, Marc Willers KC (Garden Court Chambers) and Estelle Dehon KC and Ruchi Parekh (Cornerstone Chambers).

The legal costs were raised through a Crowdfunder campaign and various fundraising activities. Costs of the Supreme Court stage were covered by Law for Change. Sarah and the Weald Action Group are very grateful to all the individuals and organisations who gave so generously.

Find out more

• Watch the recording of the hearing
• Read media coverage in the Sunday Times, BBC, ENDS report, Sky, Guardian and more.
• Read Drill or Drop’s report from the hearing: Day 1 and Day 2