Climate litigation and the rationality quagmire

October 10, 2022

Posted by: William Upton KC and Noémi Byrd

The disconnect between overarching carbon reduction requirements in the CCA 2008, and national planning policy (and, ultimately, national and local planning decisions) continues to inspire litigation. No claim has yet succeeded. The legislative framework is such that the majority of challenges can only take aim at the rationality of the decision.

R (Transport Action Network Ltd) v Secretary of State for Transport & Anor [2021] EWHC 2095 (Admin) exemplifies the problem for claimants when the empowering legislation does not refer to climate impacts. It is worth looking back at this challenge to the Road Investment Strategy 2 (“RIS2”) which was, inevitably, straightjacketed by the terms of s.1 of the Infrastructure Act 2015. That provision simply requires the Secretary of State to “have regard, in particular, to the effect of the strategy on (a) the environment” in setting the strategy. There is no requirement, on the face of it, to have regard to the effect on climate change or the Net Zero target duty.

Absent any legislative requirement, it was common ground that the Claimant had to show that the Paris Agreement Art 4 objective, the Net Zero target duty, and the likely difficulty in meeting the UK’s fourth and fifth carbon budgets under the CCA 2008, were “so obviously material” to the decision to set RIS2 that the Secretary of State was legally obliged to take them into account. In particular, the Claimant argued that the Secretary of State failed to take into account a numerical assessment of how the predicted carbon emissions from RIS2 related to carbon budgets 4 and 5, or any cumulative assessment of emissions up to 2050 (in breach, it was argued, of Article 4 of the Paris Agreement).

If there was any lingering misconception that the Court of Appeal’s celebrated finding in the Heathrow third runway challenge ([2020] EWCA Civ 214) – namely that the Paris Agreement was an “obviously material consideration” – had survived the Supreme Court’s judgment on appeal, this was firmly squashed [112]. That loss is mitigated insofar as Article 2 of the Paris Agreement (the temperature restriction objective) is concerned because the restriction is, in effect, incorporated by s.1 CCA 2008. It does, however, stymie claimants in non-EIA cases which rely on Article 4 of the Paris Agreement (the urgency objective and reduction of cumulative emissions up to 2050), as the Claimant did in this case. Holgate J observed that there is no cumulative carbon emissions reduction target for the period 2020-2050 in national legislation, against which the overall impact of any proposal could be compared [140] – even if this impact were an obviously material consideration. The only cumulative targets in the CCA 2008 are the carbon budgets which, at the time of the RIS2 decision, did not run beyond 2032. The sixth carbon budget runs until 2037, but of course there is no budget up to 2050.

There might be some limited scope for a rationality challenge in circumstances where the Claimant can demonstrate, through evidence, that a particular project or decision will patently result in “extra emissions” (R (Cox & Ors) v Oil and Gas Authority and Secretary of State (BAIES) [2022] EWHC 75 (Admin) at [126]). However, given that the carbon budgets are economy-wide, it is difficult to imagine the circumstances in which this could be convincingly evidenced.

Moreover, a stumbling block for any claim which asserts that the Secretary of State should have calculated the carbon impact of a policy or decision against the CCA 2008 target or the budgets, remains the judgment of the Court of Appeal in Packham [2020] EWCA Civ 1004 : the Government has a “good deal of latitude” in the actions it takes to attain Net Zero emissions as part of an “economy wide transition” [84-99]. That ‘strategic discretion’ hurdle is still very firmly in place.

It may be that the Environmental Impact Assessment Regulations (for as long as they remain in force) and specifically the requirement to assess the direct and indirect significant effects of a project on the climate and GHG emissions, will yet prove more fruitful for claimants. An EIA assessment is carried out on the basis of an environmental statement (“ES”) which need not include information beyond that “reasonably required” to assess the likely significant effects. The adequacy of an ES is, therefore, a matter for the decision maker subject only to review on Wednesbury grounds. This is where the claim in Finch ([2022] EWCA Civ 187), in contending that Scope 3 downstream emissions from oil wells were cumulative impacts which must be taken into account in an ES, eventually foundered. Nevertheless, the Court concluded that Scope 3 emissions were legally capable of falling within the scope of an EIA, and in his dissenting judgment Moylan LJ found that the focus of an EIA of extractive development for commercial purposes should be on the likely significant environmental effects of those commercial purposes (which include Scope 3 emissions). Finch is now under appeal to the Supreme Court. Whether the requirement to assess indirect significant effects survives the changes to environmental impact assessment in the Levelling-up and Regeneration Bill (“LURB”), remains to be seen.

Another recent judgment, the unsuccessful challenge by GOESA to the decision to permit the extension of a runway at Southampton International Airport ([2022] EWHC 1221 (Admin)), illustrates many of these problems. In EIA cases, the “substantial margin of appreciation” which is to be given to judgments based on scientific or technical expertise (Mott [2006] 1 WLR 4388) presents a formidable obstacle when the decision-maker has access to that expertise [102]. Then there are the policy uncertainties which make it next to impossible for decision-makers to assess the likely effects of emissions of any particular project against the sixth carbon budget, which is the most ambitious so far [116].

Holgate J’s observations in GOESA are salutary : it was “rightly pointed out that no criteria or thresholds had been set by which to measure the “significance” of the GHG emissions from a particular proposal. Furthermore, no one has suggested that there was any guidance for assessing the acceptability (or what the claimant sometimes called “affordability”) of that contribution, whether expressed as a percentage of national budgets or targets or
otherwise. In other words, acceptability is for the judgment of the decision-maker” [122-123].

In the absence of the kind of objective Net Zero Test called for by the CCC, any decision about whether a project is “affordable” when considered against the carbon budgets will remain a matter of judgment and subject only to Wednesbury review.

At the local planning level, while climate emergency declarations do not appear to being doing much to discourage carbon-intensive development, they are increasingly relied on in support of renewable energy generation – an approach consistent with the NPPF. Two weeks ago, South Gloucestershire Council granted temporary permission for a 49.99 MW solar farm which will provide electricity to over 14,400 homes. It is on Green Belt Land. The officer’s report noted that the scheme’s saving of 25,787 tonnes of CO2 annually would make “an appreciable contribution” to the Net Zero target in the CCA 2008. The problem remains that, in the current legal landscape, it is extremely unlikely that the converse would apply, and that the refusal of a scheme on the basis that it would generate that amount of CO2 – and thereby make an appreciable dent in the carbon budget(s) – could survive an appeal.

In our next blog, we will look at what difference the LURB could make to assessing the climate impacts of development.


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