This autumn, the government revised carbon values to bring them into line with new legally binding net zero obligations, passed in June 2019. While this may be the end of the road for the Heathrow ANPS litigation challenges of this nature are becoming increasingly common and are likely to continue.The “carbon value” of the expansion is the price of abatement required to offset the carbon emissions of the runway. However, this decision suggests that there is still a wide discretion allowed to ministers and that the bar for what counts as policy is higher than previously thought. Scottish Minsters are also obliged to consider policy, of both the Scottish and Westminster Governments, and to consider sustainable development. This decision is of interest in Scotland as much of the English law considered is reflected in Scottish legalisation. However, the Court held there was no duty to reference policies which had yet to be formulated. The final argument was that the Secretary of State should have taken into account post 2050 emissions. It would run the risk of overwhelming the public with information and reduce their ability to comment. To require a legalistic approach which covered all relevant information would be counterintuitive. The court held that the report was adequate as it was within the Secretary of State's discretion as to what information was included. It was argued that the SEA report was insufficient as it did not refer to the Paris Agreement. This report must consider the relevant environmental protection objectives established at the international, EU and domestic level. The Planning Act requires the Secretary of State to produce a strategic environmental appraisal (SEA) when preparing the ANPS. In Scotland the new Scottish purpose of planning, which has applied to development planning since 8 November 2019, including the forthcoming National Planning Framework, is ' to manage the development and use of land in the long term public interest', which includes anything which 'contributes to sustainable development'. It did not matter that they decided to assign no weight to it. However, the Supreme Court held that by considering what weight to give to the Paris Agreement the Secretary of State had discharged this obligation. It was suggested that this obligation included a thorough consideration of the Paris Agreement. The Secretary of State's obligation to consider sustainable development was also considered. The Heathrow decision suggests it will not necessarily include all ministerial statements. In Scotland, when preparing the revised National Planning Framework Scottish Ministers must ' have regard to relevant policies and strategies.' That could include Scottish and Westminster Government policies, and policies of other statutory bodies. The Paris Agreement was not Government policy. Both ministerial statements left ambiguity. It could only be formal written statements that are 'clear, unambiguous and devoid of relevant qualification'. It ruled that Government policy should be defined narrowly. It was previously held by the Court of Appeal that as the Agreement had been discussed in two ministerial statements the Agreement was consequently Government policy. While the UK is a signatory the treaty has not been incorporated into UK legislation. The Paris Agreement is a United Nations Treaty which obligates its signatories to meet ambitious targets to reduce the effects of climate change. The question asked was what constitutes Government policy? Under the Planning Act 2008 the Secretary of State is required to consider 'Government policy'. It focused its decision on the obligation on the Secretary of State to consider: In this case, the Supreme Court was asked to decide whether the Government had taken proper account of the Paris Agreement when drawing up the ANPS.

My colleague Neil considers this case here.

This held that the Secretary of State should have considered the Paris Agreement when deciding whether to allow a third runway at Heathrow.

This case appealed an earlier Court of Appeal decision. Despite considering English legislation its consideration of the Paris Agreement and climate change policies means this case may inform Scottish decisions in the future. The ANPS is the government policy which provides for the extension of Heathrow airport and supports the construction of a third runway.

The Supreme Court has recently ruled to reinstate the Airports National Policy Statement (ANPS).

Heathrow airport runway