In Jennifer Dawes v Secretary of State for the Transport Department [2023] EWHC 2352 (Admin) the High Court dismissed a challenge brought by a local campaigner on the grounds of, among others, climate change in relation to the grant of development consent for the redevelopment and reopening of Manston Airport.

Key Points

  • Public law decision makers are entitled to rely on their own unchallenged policies to deliver the outcome for which they were designed. Here the Government's Jet Zero policy was seen as capable of accelerating decarbonisation in the aviation sector and ensuring that carbon budgets were met without directly limiting aviation demand.
  • There is nothing to preclude expert evidence being provided in a decision-making or consultation process in which some of the underlying data or evidence is not disclosed on the grounds that it is commercially confidential. This omission did not render the consultation process unlawful and it was a matter for the decision maker to decide what weight should be placed on the evidence in the circumstances.
  • The court will impose high hurdles both for finding that a consultation process was so unfair as to be unlawful and for finding irrationality in a matter involving the exercise of judgment by a public law decision maker.


Manston Airport is an aviation facility located in Kent which has been used for various purposes over the years, including handling both passenger and freight traffic, but which closed in 2013.

In 2018 Riveroak Strategic Partners Limited (the Interested Party in the proceedings) submitted an application seeking a development consent order to allow for the redevelopment and reopening of Manston Airport as a dedicated air freight facility. Following an examination process where the Examining Authority recommended refusal of consent, the Defendant issued a decision in 2020 disagreeing and granting development consent for the project, but this was quashed in 2021 following a successful legal challenge.

Subsequently the Defendant initiated a reconsideration process, resulting in a second decision in August 2022 where the Defendant again determined that development consent should be granted. As part of this reconsideration process the Defendant consulted with stakeholders about certain matters and appointed an independent aviation assessor ("IA"). Stakeholders were told they would be given the opportunity to comment on the IA report, the representations received and supporting information. The IA considered that the Examining Authority's reasoning remained valid. However the Defendant disagreed.

The Claimant challenged the second grant of consent on the following grounds:

  1. Ground 1: the Claimant raised several submissions in relation to the Defendant's conclusions as to the need for the development. In particular, the Claimant argued that it was procedurally unfair for the Defendant to heavily rely on certain reports without providing access to the underlying data and without allowing the Claimant to scrutinise or make representations about these reports; and
  2. Ground 2: this ground related to climate change and, in particular, firstly, the relevance of the sixth carbon budget. Apart from a single paragraph in the decision letter, the Defendant did not mention the sixth carbon budget and its implications for the development.

Secondly, the Claimant challenged the Defendant's reliance upon the Decarbonising Transport Plan ("DTP") and the Jet Zero Strategy ("JZS") in concluding that the development would have a neutral impact upon climate change. The Claimant pointed to the fact that modelling work undertaken for the JZS did not include modelling of capacity expansion at Manston Airport and asserted that the JZS contains only vague proposals and assumptions that do not provide a robust basis to make informed decisions.


Ground 1

The Claimant focused on a report in support of the application by the Interested Party which contained analysis of demand and concluded that Manston could "play a vital role in helping Britain's connectedness and trade with the rest of the world". Certain underlying data was not disclosed due to reasons of commercial sensitivity. The Examining Authority had considered that reduced weight should be given to this report and was not convinced that the demand for air freight could not be met by other airports. The Claimant argued that the report was of such critical importance to the ultimate decision that there was a particularly acute need in the interests of fairness for the underlying evidence to be disclosed. In the absence of that material being disclosed, stakeholders were said to be hamstrung in their ability to address the validity of the report's conclusions

Dove J agreed that the report was a material consideration in the decision-making process, in particular, on the question of demand and need. He explained that there is nothing to preclude expert evidence being provided in a decision-making process of this kind in which some of the underlying data or evidence is not disclosed on the grounds that it is commercially confidential and cannot be put into the public domain. It was not disputed that the report remained relevant and therefore the challenge boiled down to what weight should have been attached to the report in the light of the non-disclosure. This was ultimately a matter for the Defendant who decided that the withholding of commercially sensitive material was justified and did not affect the weight to be given to the report. In those circumstances Dove J did not consider that fairness required the provision of the additional material.

The Claimant also raised other points concerning the process. Dove J accepted that the consultation process was "not perfect", but applied the test of asking not merely whether something went wrong, but whether something went clearly and radically wrong. He was not persuaded that the flaws had reached this required standard.

Ground 1 also contained other aspects such as an irrationality challenge. Dove J observed that the decision which the Defendant had to reach in relation to demand forecasts and overall need required a judgment to be undertaken in respect of a variety of types of evidence before him and the Claimant therefore faced a daunting task to persuade the court that it was irrational. This high hurdle had not been met in this case.

Ground 2

In relation to climate change, the Interested Party's 2018 environmental statement had concluded that the effect of greenhouse gas emissions from the proposed development on the climate was "not significant". By contrast, the Examining Authority's position was that the project's aviation emissions would have a material impact on the Government's ability to meet its carbon reduction targets, including carbon budgets, and that this weighed against the granting of development consent.

Dove J considered that there was no error in the Defendant's decision in relation to the sixth carbon budget and the Defendant's approach was adequately, if succinctly, explained in the decision.

The Defendant relied on the DTP and JZS policies as measures that would accelerate decarbonisation in the aviation sector, setting out the pathway to net zero. The DTP for example states that the combining of projections for domestic and international aviation emissions through the inclusion of international aviation in the UK's sixth carbon budget in 2033 means that aviation emissions will continue to fall to 2050. JZS states that Jet Zero can be achieved without Government intervention to directly limit aviation growth and sets out policies and a mix of measures to ensure the UK aviation sector reaches net zero by 2050. The Defendant considered that these policies will ensure decarbonisation targets for the sector and the legislated carbon budgets can be met without directly limiting aviation demand, and therefore did not accept the Examining Authority's view that carbon emissions should be afforded moderate weight against the project in the overall balance, instead concluding that it should instead be given neutral weight at most.

The court considered that this was a permissible legal approach. The Defendant was entitled to rely on these unchallenged policies to deliver the outcome for which they were designed, in particular, achieving the carbon budgets without impacting aviation demand. The modelling for JZS, when seen in context, was not intended to be a firm prediction but simply a tool, and therefore the omission of Manston from that modelling was not of significance.


This decision is another notable case in the aviation context raising climate change considerations. It highlights the increasing importance of environmental considerations in large-scale projects, and their frequent use as grounds for judicial review, as the judgment touches on climate change concerns, emissions modelling, and adherence to carbon budgets.

Ultimately however the court followed the established trend in judicial review cases of deferring to the judgment of the decision maker. The court did not delve into the detail of whether DTP and JZS would in fact achieve their aims but considered it reasonable for the Secretary of State to proceed on that assumption.

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