The Inner House of the Court of Session, Scotland's highest court, previously found in favour of the Scottish ministers, which granted permits for the projects in October 2014. Environmental charity the Royal Society for the Protection of Birds (RSPB), which had challenged the ministers on the basis of the potential impact of the wind farms on certain species of migratory seabirds, applied to the Supreme Court for permission to further appeal.
The Supreme Court has now rejected that application, following a review by three senior judges of written submissions by the parties.
"[T]he application does not raise an arguable point of law of general public importance which ought to be considered at this time, bearing in mind that he case has already been the subject of judicial decision and reviewed on appeal," the Supreme Court said.
Planning and environmental law expert Gordon McCreath of Pinsent Masons, the law firm behind Out-Law.com, described the decision as "a firm endorsement of the clarity and common sense of the Inner House judgment under appeal".
"At last Scottish offshore wind will now see some significant moves forward, beyond the success of the Beatrice wind farm in the Moray Firth," he said. "The Inner House judgment that RSPB sought to appeal here was a welcome return to clear, pragmatic legal interpretation after some difficult reasoning at first instance. That the Supreme Court sees no need to reopen that interpretation is not unexpected, but it is very welcome nonetheless."
"The wait has been a long one, but the renewables industry can now take these projects through to construction in what should be a more streamlined process for obtaining pre-build approvals, enjoying the benefit of the well-regarded precedents developed by first-mover Beatrice," he said.
The case also "highlights the need for further reform of the judicial review process, both north and south of the border", according to energy law expert Gareth Phillips of Pinsent Masons.
"It should not be acceptable that an offshore wind farm that would be classified as 'nationally significant' under the planning system in England and Wales be delayed for three years while the courts consider a challenge," he said. "Objectors well know that the delay caused by bringing a claim can be enough to end a project regardless of the merits of their claim."
"It is just as important to have a fair, but expeditious, legal challenge process as it is to have an expeditious consent process. Without the former, the latter is prejudiced – and so too international investment in a strong offshore wind industry," he said.
The dispute arose in relation to four planned wind farms in the Firth of Forth and the Firth of Tay, on the east coast of Scotland: Inch Cape, Neart Na Gaoithe, Seagreen Alpha and Seagreen Bravo. As a result of advances in offshore wind technology, the total number of planned turbines is now lower than it was when planning permission was granted by the Scottish ministers.
The RSPB had claimed that, when granting planning permission, the Scottish ministers had failed to properly comply with the Environmental Impact Assessment (EIA) regulations. It also claimed that the ministers had not carried out the necessary 'appropriate assessment' of the suitability of the sites, and that they had not given appropriate weight to advice received from conservation bodies during the consultation process.
The Inner House ruled in favour of the Scottish ministers in May. It found that the developers of each of the four planned projects had obtained a scoping opinion from the ministers ahead of their formal applications, in each case accompanied by a "very substantial" environmental statement. In addition, all publication and consultation requirements were complied with, and there was "no scope" in the relevant regulations requiring the developers to supply any further information to the public and to environmental bodies.