Today’s court of appeal ruling that the government’s decision to approve Heathrow expansion was unlawful on environmental grounds has major implications for all proposed UK infrastructure projects going forward, says Julian Francis.

Heathrow’s long road to expansion and the completion of the third runway has hit another bump today as the court of appeal has ruled that the government’s decision to approve Heathrow’s expansion was unlawful because it did not take UK climate commitments into account. 

In a landmark ruling that will have implications for all prosed UK infrastructure projects going forward, three judges stated that the expansion of the airport in its current form was incompatible with the government’s climate change commitments under the Paris Agreement. The court upheld the view that Section 5(8) of the Planning Act required the government in its policy statement to explain how the decision fitted in with the stated intention of the government to promote the mitigation of, and adaptation to, climate change as required by the Paris Agreement. 

Although the court did not rule that Heathrow expansion could not go ahead per se, it did invalidate the current national policy statement forcing Heathrow and the government to return to the starting blocks. 

This judgement will have profound implications for our industry as Heathrow expansion was overwhelmingly backed by MPs in a Commons vote in June 2018, with 415 in favour and only 119 against. As a result, Heathrow is now in the process of applying for a development consent order which it hopes to lodge at the end of the year with a view to opening the new runway by 2029 at the latest. 

Furthermore, business leaders are also likely to come out strongly against this ruling as they have been calling for the expansion of Heathrow for more than 20 years now. It will also have an impact in other common law jurisdictions who will look to this judgement as establishing a legal framework around the delivery of national emission targets.

So, what does this mean for our industry? 

Well, from now on, every infrastructure spending decision in the UK could face a legal challenge if it doesn't comply with the Climate Change Act, which mandates virtually zero emissions by 2050. It's not clear at present that this was an outcome that MPs intended when they signed up to the 2050 target, but in today's court ruling, it’s what they've got. The judgement’s implications are clearly wider the just Heathrow as the judges have stated that climate change must be kept at the heart of all planning decisions and that developers and public authorities can be held to account if their proposed schemes negatively impact UK climate change commitments. 

So, I predict that the government will now be looking at ways to mitigate the implications of the judgement. 

In the short term, however, Heathrow faces limbo as the prime minister has announced that he does not plan to appeal against the ruling which will undoubtedly also call into question aviation expansion in the UK generally, as there is currently no viable technical fix to make planes zero-carbon and carbon offsetting schemes proposed by the aviation industry are contentious.

Julian Francis is the director of policy and external affairs at the Association for Consultancy and Engineering.