The Heathrow judgment: what we learned about climate change law

June 25, 2019

Posted by: Frances Lawson

The High Court judgment in the Heathrow third runway case is arguably the most extensive judicial reasoning on current UK climate change law to date.

Linked cases brought by five London boroughs, the London Mayor, environmental groups Friends of the Earth, Plan B Earth and Greenpeace, and a member of the public, challenged the 26 June 2018 decision of the Secretary of State for Transport to designate a third runway at Heathrow as Government policy in the Airports National Policy Statement (ANPS) under section 5 of the Planning Act 2008 (PA 2008).

The ten claimants, brought together in four separate claims, sought judicial review of the designation on 22 grounds, a further 13 sub-grounds, and 26 sub-issues. The grounds included the Climate Change Act 2008 (CCA 2008) and its relationship to the 2016 Paris Agreement, the law governing air quality, strategic environmental assessment (SEA), and the Human Rights Act 1998 (HRA 1998).

Lord Justice Hickinbottom and Mr Justice Holgate heard full arguments on all issues, stressing that the hearing “was concerned only with the legality (and not the merits) of the ANPS”. [669]

The judgment found only two grounds (habitats; consultation) and two-sub-grounds (SEA) as arguable, and rejected the substantive application in those, and dismissed all other 20 grounds as not arguable. [667] A copy of the full judgment can be found here.

The claimants were represented by QCs, including Nigel Pleming of 39 Essex Chambers, and David Wolfe of Matrix Chambers, making submissions in the context that a choice of third runway for Heathrow will produce “the highest carbon emissions in absolute terms” [596] as opposed to a second runway for Gatwick which the Airports Commission (AC) concluded “was associated with the lowest additional emissions”. [594]

The ANPS commits the Government to delivering the third runway “within the UK’s climate change obligations” [595] and air quality obligations [82], yet in 2026, when the new runway is due to be open [242], the Court heard evidence from the Climate Change Committee (CCC) 2016 Progress Report that:

Current policy in the UK is not enough to deliver the existing carbon budgets that Parliament has set … Current policies would at best deliver around half of the emissions reductions required by 2030, with no current policies to address the other half” [583].

Similarly, even if aviation emissions in 2050 were no higher than the level of 2005 (known as the Aviation Target) and are included at this level in the aggregate 2050 carbon budget, as they are required to be [572], then compliance with the 2050 target can only be achieved through reducing emissions in other sectors by 85% on 1990 levels [574].

The Court heard CCC advice that this reduction of 85% “is at the limit of what is feasible, with limited confidence about the scope for going beyond this” [574].

The Court also heard that in responding to CCC concerns over the impact of a third runway at Heathrow, the Secretary of State reminded the CCC “that the proposed ANPS made clear that an increase in carbon emissions that would have a material impact on the ability of Government to meet its carbon reduction targets would be a reason to refuse development consent; and the Government was confident that the measures and requirements outlined in the ANPS provided a strong basis for mitigating the environmental impacts of expansion. He indicated that these issues would be considered as part of the Aviation Strategy” [601].

In short, then, even on facts that appear to offer a strong case for the application of the precautionary principle to a major development, and even with some of London’s most senior barristers lined up to argue that case, the dismissal of all 22 grounds in Heathrow offers a drastic illustration of the limits of public law to affect Government climate change policy.

That said, the case is nonetheless a valuable addition to the fledgling common law on climate change, as well as an authority (for now) on what that law is, what it is not, and where Government obligation and liability in climate change lie. Below are some of the main points from the case as related to UK climate change law.


What laws govern the planning of a project that will impact on climate change?

Part 2, section 5(1) of the PA 2008 empowers the Secretary of State to designate a National Policy Statement (NPS) for development falling within the scope of the Act [26].

Section 5(8) includes the imperative that an NPS “must (in particular) include an explanation of how the policy set out in the statement takes account of Government policy relating to the mitigation of, and adaptation to, climate change” [27].

Section 7(2) requires the Secretary of State to “carry out such consultation, and arrange for such publicity, as the Secretary of State thinks appropriate in relation to the proposal.” As the Court noted: “That gives the Secretary of State a broad discretion” [124].
And as formulated in the Gunning principles, endorsed by the Supreme Court in Moseley [2014], “the product of consultation must be conscientiously taken into account in finalising any statutory proposals” [125].

In addition, under the heading “Sustainable development”, section 10(1)–(3) of the PA 2008 says the Secretary of State “must” in exercising functions under section 5, “do so with the objective of contributing to the achievement of sustainable development”, which includes an obligation to “have regard to the desirability of … mitigating, and adapting to, climate change” [28].

Sustainable development is not defined in the CCA 2008, but is found in paragraph 7 of the National Planning Policy Framework (July 2018) (the NPPF), which adopts the definition used in Resolution 42/187 of the United Nations General Assembly (“the Brundtland definition”) stating:
At a very high level, the objective of sustainable development can be summarised as meeting the needs of the present without compromising the ability of future generations to meet their own needs” [635].

The NPPF goes on to say that achieving sustainable development means that a planning system has three overarching objectives, which are interdependent and need to be pursued in mutually supportive ways, namely an environmental objective, an economic objective and a social objective (paragraph 8). [635]

Under section 104(4) PA 2008, the Secretary of State is constrained when determining an application for a Development Consent Order (DCO) arising from an NPS if “deciding the application in accordance with any relevant [NPS] would lead to the United Kingdom being in breach of any of its international obligations.” [37]

In addition, there is a requirement to carry out a strategic environmental assessment (SEA) under Directive 2001/42/EC of the European Parliament and of the Council on the assessment of the effects of certain plans and programmes on the environment (the SEA Directive) as transposed by the Environmental Assessment of Plans and Programmes Regulations 2004 (SI 2004 No 1633) (the SEA Regulations). [30]
Regulation 12(2) of the SEA Regulations also requires that the SEA report “identify, describe and evaluate the likely significant effects on the environment of (a) implementing the plan or programme; and (b) reasonable alternatives taking into account the objectives and the geographical scope of the plan or programme” [399].

Furthermore, under normal planning procedures an environmental impact assessment (EIA) is also required under Directive 2011/92/EU of the European Parliament and of the Council of 13 December 2011 on the assessment of the effects of certain public and private projects on the environment as amended (the EIA Directive), as currently transposed by the Town and Country Planning (Environmental Impact Assessment) Regulations 2017 (SI 2017 No 571).

However, the EIA Regulations only apply when there was a particular development for which development consent was sought, at the Development Consent Order (DCO) stage. [378] The SEA Regulations concern the environmental impact of plans and programmes, and thus applied to the ANPS [378].

How is the adequacy of Government planning that impacts climate change tested in public law?

The Heathrow judgment confirmed that the public law test for the compliance of Government decision making under the substantive requirements set out above remains the 1948 Wednesbury unreasonable standard, being a decision “so unreasonable that no reasonable person acting reasonably could have made it.

The contemporary authority is the so-called Blewett approach from 2003, dealing with the legal adequacy of an environmental statement for the purposes of an EIA of a development project under the EIA Directive and Regulations. In this regard, the Court in Heathrow noted that: “It is said that the test under the Blewett approach for judging whether an environmental statement is legally inadequate (i.e. non-compliant with the Directive) comes from the final sentence of the passage cited, namely the document must be so deficient that it could not reasonably be described as an environmental statement.” [404] It additionally commented that: “There will be cases where the document purporting to be an environmental statement is so deficient that it could not reasonably be described as an environmental statement as defined by the Regulations…, but they are likely to be few and far between.” [403]

The court heard submissions that Blewett does not apply when determining whether an environmental report complies with the SEA Directive, because such a report must comply with the mandatory requirements of the SEA Directive, for which the test is one of “sufficient quality”, which involves ensuring that it is “based on proper information and expertise and covers all potential effects of the plan or programme in question” (see Forest Heath [2011])

The court considered the leading authorities on the issue, including Forest Heath [2011], Blewett [2004], Shadwell [2013], Edwards [2009], St Albans [2009], Ashdown Forest [2016], Seaport Investments [2008], and Gladman Developments [2014] and concluded, “it is plain that the Blewett approach is not a freestanding standard or principle: it is no more and no less than a practical application of conventional Wednesbury principles of judicial review.”

In particular, it stated: “The information in article 5(1) and Annex I which is to be included in an environmental report is that which “may reasonably be required (article 5(2)). That connotes a judgment on the part of the authority responsible for preparing the plan or programme. Such a judgment is a matter for the evaluative assessment of the authority subject only to review on normal public law principles, including Wednesbury unreasonableness.” [433]

Where an authority fails to give any consideration at all to a matter which it is explicitly required by the SEA Directive to address, such as whether there are reasonable alternatives to the proposed policy, the court may conclude that there has been non-compliance with the Directive. Otherwise, decisions on the inclusion or non-inclusion in the environmental report of information on a particular subject, or the nature or level of detail of that information, or the nature or extent of the analysis carried out, are matters of judgment for the plan-making authority … The established principle is that the decision-maker’s judgment in such circumstances can only be challenged on the grounds of irrationality … The Blewett approach is simply an application of this public law principle.” [434]

What are the UK’s binding climate change laws?

The court confirmed that the only legally binding targets directly related to climate change that the UK Government must meet are those set out in the CCA 2008.

Section 1 sets the overall target: “It is the duty of the Secretary of State to ensure that the net carbon account for the year 2050 is at least 80% lower than the 1990 baseline”. [566]

Section 5(1)(a) is the only other binding target set by the Act itself, being a carbon budget “for the budgetary period including the year 2020, must be such that the annual equivalent of the carbon budget for the period is at least 26% lower than the 1990 baseline”.

Section 4(1)(a)(b) requires the Secretary of State to “set for each succeeding period of five years beginning with the period 2008-2012 … an amount for the net UK carbon account … and to ensure that the net UK carbon account for a budgetary period does not exceed the carbon budget.”

Is the Paris Agreement target legally binding on the UK?

No. The court found the CCA 2008 was Parliament’s response to the international commitment, under the UNFCCC and the subsequent Kyoto Protocol, to keep global temperature rise to 2°C above pre-industrial levels in 2050. [562-566]

The court confirmed that under the UK’s dualist legal system international law or an international treaty only has legal force at the domestic level after it has been implemented by a national statute. [606]

In essence, then, the CCA 2008 was the UK’s implementation of Kyoto. However, the Court made clear that the more ambitious target under the 2016 Paris Agreement of holding global warming to 1.5°C, and to “well below” 2°C, has not been incorporated by the CCA 2008, and so is not legally binding.

Plan B Earth pressed the Secretary of State for BEIS to revise the 2050 carbon target under the CCA 2008 on the basis that, following the Paris Agreement, he was obliged to do so [584]. That argument was rejected by the court: “The Paris Agreement imposes no obligation upon any individual state to limit global temperatures or to implement the objective in any particular way. It expresses global objectives, and aspirations in respect of national contributions to meet those objectives; and it obliges each state party to “prepare, communicate and maintain successive nationally determined contributions that it intends to achieve’” [607].

In designating the ANPS in favour of Heathrow, the Secretary of State did not err in “failing to take into account the Paris Agreement, or the premise upon which that Agreement was made namely that the temperature rise should be limited to 1.5°C and “well below” 2°C … Nor was he otherwise obliged to have taken into account the Paris Agreement limits or the evolving knowledge and analysis of climate change that resulted in that Agreement.” [619]

Section 2(1) CCA 2008 empowers the Secretary of State to amend the target percentage, “if it appears to him that there have been significant developments in scientific knowledge about climate change since the passing of the Act, or developments in European or international law or policy.” (section 2(2) and (3)) [567]. But, following Supperstone J’s refusal of permission at an oral hearing ([2018] EWHC 1892 (Admin)), the Court held section 2 confers a power to amend the 2050 target, not a duty [585]. Thus, for the public law purposes of deciding the legality of Government decision making on climate change, the Paris Agreement target of 1.5°C can be lawfully ignored:

Nor is there anything in the PA 2008 or elsewhere that suggests that he was required to take international commitments into account. In our view – and clearly – international commitments were a consideration in respect of which he had a discretion as to whether he took them into account or not.” [647]

Does climate change engage human rights law?

Not for the purposes of public law, yet.

The court noted that the link between the use of fossil fuels and the rise in global temperatures “is now generally accepted – and accepted by all parties before the court”, and “has resulted in (amongst other things) sea level change; a decline in glaciers, the Antarctic ice sheet and Arctic sea ice; alterations to various ecosystems; and in some areas a threat to food and water supplies. It is potentially catastrophic.” [559]

The judgment also included the main conclusion of the IPCC Special Report on Global Warming of 1.5°C published on 8 October 2018. The report concludes that limiting global warming to 1.5°C above pre-industrial levels, as opposed to 2°C, would significantly reduce the risks of “challenging impacts” on ecosystems and human health and well-being; and that meeting a 1.5°C target is possible but would require “deep emissions reductions” and “rapid, far-reaching.” [590]

For global warming to be limited to 1.5°C, global net emissions of CO2 would need to fall by about 45% from 2010 levels by 2030, reaching zero by 2050 [590]. The UK’s 5th carbon budget for the period covering 2030 aims to meet that higher target of 45% reductions on 2010 levels.
However, just a few paragraphs earlier, the court included the CCC’s own 2016 Progress Report that current UK Government policies “would at best deliver around half of the emissions reductions required by 2030, with no current policies to address the other half. This carbon policy gap must be closed to meet the existing carbon budgets, and to prepare for the 2050 target and net zero emissions in the longer term.” [583]
In other words, the court recognises evidence that current Government policy on climate change increases the risk of exposing future citizens to grave and foreseeable harm. However, as noted above, there is nothing unlawful about the UK Government failing to pursue the safer target of 1.5°C, and the Court was brisk in dismissing attempts to use human rights law as grounds of challenge.

The judgment cites Supperstone J that the alleged failure of the Secretary of State to take preventative measures in the face of climate change was not arguably a breach of article 2 or 8, or of article 1 of the First Protocol (“A1P1) to, the European Convention on Human Rights (“ECHR”), and thus the Human Rights Act 1998. [585]

And in dismissing the alleged breach by the ANPS designation of Article 8 of the ECHR, and thus the Human Rights Act, the Court held that “it is well-established that the state has a wide margin of discretion in the assessment of where the balance between rights and interests (including the public interest) lies” [664]. It went on that this is: “Particularly given that the rights and interests of those residents will be at the forefront of the planning consideration of the scheme at the DCO stage – and given the scope of section 104 (see paragraph 37 above) – it is simply not arguable that, in designating the ANPS, the Secretary of State breached either article 8 or A1P1.” [664]

Is there a legally binding target for air pollution?

Effectively, yes. The judgment in Heathrow clarifies that if value limits on air pollution are breached, the Government is legally obliged to produce a plan and timetable to meet the target, and that plan must contain measures to ensure local authorities do so. Indeed, it is arguable that air quality laws now form part of the UK’s binding law on climate change, as many of the pollutants covered by air quality laws are also greenhouse gases.

The Air Quality Standards Regulations 2010 transposed Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 (the Air Quality Directive) on ambient air quality and cleaner air for Europe. Article 1(1) of the Directive imposes “binding commitments” on the UK for “ambient air quality to avoid, prevent or reduce harmful effects on human health and the environment as a whole”. [220]

Article 13 of the Directive imposes limit values on certain air pollutants, and courts have subsequently ruled the exceeding of these limits is “in itself sufficient for a finding to be made that there has been an infringement of article 13” [225]

The Government’s Air Quality Plan (AQP) has three times been declared unlawful by the courts on grounds that it failed to contain measures sufficient to ensure compliance with the Air Quality Standards Regulations 2010 [230-232].

The court heard that in 2010, the year the UK’s Air Quality Regulations was incorporated into law, 40 of the 43 UK zones subject to the Regulations were in breach of at least one of the limit values for Nitrogen Dioxide (NO2) [230]. Under the EU’s Air Quality Directive, NO2 limit values were to be achieved by 1 January 2010 [226]. After seeking an extension of time from the European Commission, the Secretary of State for the Environment was made subject of a mandatory order of the Supreme Court requiring him to prepare new AQPs in accordance with a defined timetable (ClientEarth [2015]).

The second AQP was published in December 2015, but it too was challenged and held by Garnham J to be deficient (ClientEarth [2016]). He made an order that the SSE must publish an AQP which complied with the Air Quality Directive and Regulations by 31 July 2017 [231].

That third AQP was published on 26 July 2017. It too was challenged, and Garnham J again found it to be deficient in that, although 45 local authorities (none of which was an authority concerned with these claims) were expected to achieve compliance within three years, there was no requirement that they did so and no measures to ensure they did so. The AQP 2017 was therefore found to be unlawful; but it was not quashed. It was remitted to the Secretary of State for Environment for revision to cure the identified legal defect. The AQP 2017 is therefore the current plan [232]. The AQP 2017 is said to be likely to achieve compliance with the limit values in London in 2025. [233]

In his judgments, Garnham J found – and firmly emphasised – that, where a Member State is in breach of article 13(1), it is required to prepare an AQP in accordance with the Air Quality Directive, including measures to ensure that the period the limit values is exceeded is as short as possible. In each of the ClientEarth cases, the SSE was directed to prepare an AQP that complied with the Directive within a particular period [234]. However, in the 2019 case of Shirley, the Court of Appeal held that a “demonstrable breach of article 13 does not generate some unspecified obligation beyond the preparation and implementation of an [AQP] that complies with article 23” [235].

The Heathrow judgment confirmed that, “the Court of Appeal made clear that nothing in the Air Quality Directive requires an application for consent for development which may add to the burden of pollutants to be rejected simply because of a Member State’s failure to comply with the requirements of article 13” [237].

In other words, even if a development like the third runway at Heathrow will add to air pollution, and the UK is already in breach of its own Air Quality Regulations, that in itself is not sufficient reason that the project cannot lawfully proceed.

The Hillingdon Claimants challenge the ANPS’s approach and conclusion in respect of air quality on five grounds, including:

ii) Ground 4 : In reaching the conclusion that the NWR Scheme could be undertaken without a breach of the UK’s obligations under the Air Quality Directive, the Secretary of State failed to apply the precautionary principle.

iii) Ground 5 : It was irrational to adopt and designate the ANPS in circumstances in which it was known that, if constructed and used to full capacity from 2026, there would be a high risk that the air quality obligations will be breached in the period 2026-30. [255]

A report in May 2015 by external experts, which conducted studies and analyses at the behest of the Airports Commission on air quality and noise impact, “concluded that the NWR Scheme (the third runway) would not cause any new exceedances of the limit level or air quality objective for NO2” [240].

A further report in 2017 projected that Greater London with the third runway would be compliant with the Air Quality Regulations limit values by the time the new runway is due to open in 2026 [242] and that the risk was “primarily dependent upon action to reduce emissions from road vehicles on the wider road network not upon the contribution from any airport expansion” [259].

In a somewhat Kafka-esq paragraph of judgment, the Court in Heathrow held that there was “no scope for the exercise of the precautionary principle” because:

there is no possibility of there being a breach of the air quality requirements under the ANPS in practice, because the policy itself expressly provides that “expansion must be deliverable… in accordance with legal obligations on air quality” (paragraph 2.8) … There is no risk: as a policy, the ANPS cannot result in any possible breach of the UK’s obligations under the Air Quality Directive.” [265]

Do emissions from aviation count towards the UK’s carbon budgets?

The court in Heathrow noted that section 10(2) CCA 2008 sets out various matters which are required to be taken into account when the Secretary of State sets, or the CCC advises upon, any carbon budget, including: “(i) the estimated amount of reportable emissions from international aviation and international shipping” [570].

The court continued: “Therefore, although for the purposes of the CCA 2008 emissions from GHGs from international aviation do not generally count as emissions from UK sources (section 30(1)), by virtue of section 10(2)(i), in relation to any carbon budget, the Secretary of State for BEIS and CCC must take such emissions into account” [571].

However, the Aviation Target was confirmed as not UK Government policy for the purposes of the ANPS designation. [631]

The court heard that: “The CCC has advised that, to meet the 2050 target on that basis, emissions from UK aviation (domestic and international) in 2050 should be no higher than 2005 levels, i.e. 37.5 megatons (million tonnes) of CO2 (MtCO2). This is referred to by the Claimants as “the Aviation Target”. However, the APF explains that the Government decided not to take a decision on whether to include international aviation emissions in its carbon budgets, simply leaving sufficient headroom in those budgets consistent with meeting the 2050 target including such emissions, but otherwise deferring a decision for consideration as part of the emerging Aviation Strategy. The Aviation Strategy is due tore-examine how the aviation sector can best contribute its fair share to emissions reductions at both UK and global level” (paragraph 9 of the Climate Change Annex to the Agreed Statement). It is due to be finalised and adopted later this year” [572].

Co-authored by Frances Lawson and Hugh Macleod


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