Air pollution levels in the UK have been declared “unlawful” in a High Court ruling, which is the third time the government has lost a legal judgement on the issue.

Environmental lawyers from ClientEarth launched a legal challenge against the government last month.

And the landmark ruling has been welcomed by campaigners, as a signal that it will force urgent changes to plans to tackle illegal levels of air pollution in the country. 

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The case was about the harmful levels of nitrogen dioxide in the air, which is predominantly emitted by vehicles.

Mr Justice Garnham, the judge for the case, found that the government’s current plans are “seriously flawed,” and ruled that more action is needed in 45 local authorities in England as well as in Wales. 

“This history of this litigation shows that good faith, hard work, and sincere promises are not enough and it seems court must keep the pressure on to ensure compliance is actually achieved,” he said. 

This is the third time the courts have ruled that Ministers' plans on air quality are so bad they're illegal. Govt must now use every tool in the box to clean up our choking cities. https://t.co/KI7QGcAYyM

— Mary Creagh (@MaryCreaghMP) February 21, 2018

He added: ““The Environment Secretary must ensure that, in each of the 45 areas, steps are taken to achieve compliance as soon as possible, by the quickest route possible and by a means that makes that outcome likely.”

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Following the ruling — described as “wholly exceptional” by lawyers — the courts will now oversee the issue, rather than ministers, according to the Guardian. 

“The judge has effectively allowed us to bring this matter straight back to court without delay if the government continues to fall short of its duties,” said Anna Heslop, a lawyer with ClientEarth.

The judge did, however, reject ClientEarth’s case for five cities, including London, and described the approach to those cities as “sensible, rational, and lawful.”

A spokesperson from the Department for the Environment, Farming, and Rural Affairs, said: “We are pleased that the judge dismissed two of the three complaints. The judge found that our modelling is compliant and that our approach to areas with major air quality problems is ‘sensible, rational, and lawful’.” 

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They added that the court had asked them to “go further in areas with less severe air quality problems.” 

“We had previously considered that it was sufficient to take a pragmatic, less formal approach to such areas,” they continued. “However, in view of the court’s judgement, we are happy to take a more formal line with them.” 

Earlier plans had also been branded illegal by courts, because they didn’t adequately tackle air pollution in the UK.

The court previously heard that levels were still too high in 37 out of 43 zones across the country — 8 years after the UK was found to be in breach of the legal limits. 

The government’s most recent plan involves earmarking £255 million to help local authorities improve air quality, according to the Independent, and proposals to end the sale of petrol and diesel cars by 2040. 

Air pollution is a key issue within the UK, where it is estimated to lead to the deaths of 40,000 people every year. 

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“Millions of people in the UK live with illegally high levels of air pollution, which results in 40,000 early deaths every year,” said Mary Creagh, chair of the Environmental Audit Committee. 

“Ministers’ shambolic attempts to tackle this means this is the third time the courts have ordered the government to come up with a new plan,” she said. “The government must now use every tool in the box to clean up our choking cities.” 

Green MEP Keith Taylor added: “Instead of confronting their moral and legal duty to protect our health, ministers have prioritised throwing taxpayers’ cash away fighting in the courts against taking even the most basic action needed to bring our air within EU air pollution limits.” 

James Beard, climate and transport specialist at WWF, recommended the government bring forward its plan to ban diesel and petrol cars to 2030, reported the Independent. 

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At the end of January, Britain and eight other EU member states — including Germany, Spain, France, and Italy — were threatened with action unless they could prove they would crack down on air pollution, to bring it in line with EU air pollution laws. 

The warning came as London met its legal air pollution limit for the year, less than a month in. Elsewhere in the UK, toxic air has been at illegal level in most urban areas since 2010. 

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