The U.K. Court of Appeal has ruled that the government’s plan to build a third runway at the country’s largest airport is illegal on the grounds that it ignored climate change commitments.
In the court’s landmark decision, judges expressly cited the 2015 Paris Agreement as grounds for the ruling.
In their summary, the judges said: “The Paris Agreement ought to have been taken into account by the Secretary of State in the preparation of the ANPS [Airports National Policy Statement] and an explanation given as to how it was taken into account, but it was not.”
Ignoring the Paris Agreement, the judges said, was “legally fatal” to the plan.
The court further noted that: “The issue of climate change is a matter of profound national and international importance of great concern to the public—and, indeed, to the Government of the United Kingdom and many other national governments, as is demonstrated by their commitment to the Paris Agreement.”
By using the Paris Agreement as the legal basis for its decision, the Court of Appeal’s ruling could have far-reaching implications for other large-scale projects in the U.K., which last year passed a law that it will cut carbon emissions to net zero by 2050.
The ruling was met with scenes of jubilation outside the Royal Courts of Justice in London, where activists and politicians who have been campaigning against the runway popped bottles of champagne to celebrate the victory.
Heathrow, one of the world’s largest airports by passenger footfall, has been planning for a new runway since at least 2006, when the then-Labour government backed plans to expand the airport. Since then, the plans have gone through a series of changes and setbacks up until 2018, when the Conservative government gave the current plan the green light.
But that decision was challenged by the not-for-profit organisation Plan B, which takes legal action against decisions that contribute to climate change. Launching its case against the runway scheme, Plan B said: “On the one hand there is the U.K. Government’s policy to expand aviation, one of the most polluting forms of transport. On the other there is its policy on climate change. It can have one or the other but not both.” The case began in March 2019.
Heathrow said it would appeal today’s decision.
“We will appeal to the Supreme Court on this one issue and are confident that we will be successful. In the meantime, we are ready to work with the government to fix the issue that the court has raised,” a spokesperson said.
Reaction from campaigners to the ruling was joyful. Will Rundle, head of legal at Friends of the Earth, said: “We are delighted with the Court of Appeal’s ruling, which goes to show the massive importance of the legal system to check the clear abuse of state power by government, such as in this case.
“Shockingly, this case revealed that the government accepted legal advice that it should not consider the Paris Agreement when giving the third runway the go-ahead. The Court has said very clearly that was illegal.”
Rundle highlighted the groundbreaking nature of the case, saying: “This judgment has exciting wider implications for keeping climate change at the heart of all planning decisions.”
Meanwhile, John Sauven, Executive Director of Greenpeace UK, said: “Boris Johnson should now put Heathrow out of its misery and cancel the third runway once and for all. No ifs, no buts, no lies, no u-turns.”
It is not yet known whether the government will continue to support the plan in its current form, though in 2015, now-Prime Minister Boris Johnson famously promised to “lie down in front of the bulldozers” to prevent the runway from being built.
Other prominent Conservative voices have criticized the ruling. In a tweet, former chancellor George Osborne said:
“Judges kill off Heathrow 3rd runway and Britain getting the modern air transport infrastructure we need, despite the elected Parliament voting for it overwhelmingly. Presumably this is the kind of overreaching undemocratic judicial activism Boris wants to curb … or perhaps not”