The High Court has rejected a challenge to An Coimisiún Pleanála’s approval of the proposed Slane bypass after finding that the applicant had not proved the Commission lacked the expertise required to assess the project’s environmental impacts.
John Rogers sought judicial review of the Commission’s 27 June 2025 decision approving Meath County Council’s road scheme, subject to conditions. The project includes new bridges, roundabouts, major excavation works and changes around Slane village and the River Boyne.
Mr Rogers argued that EU and Irish law required the Commission to have, or have access to, sufficient expertise to examine the council’s environmental impact assessment report. His concerns focused particularly on hydrology and hydrogeology, including possible effects on groundwater-dependent petrifying springs and tufa habitats near Crewbane Marsh.
Mr Justice Nolan said the obligation to have sufficient expertise was an independent legal requirement and could be raised in the judicial review even though it had not been advanced during the planning process. He also found that Mr Rogers had pleaded that case adequately.
However, the judge refused to admit two expert reports introduced in a late replying affidavit, finding they sought to expand the case and advance a merits-based disagreement after the appropriate stage for evidence had passed.
The court also rejected an argument that the Commission breached its duty of candour by declining, shortly before the hearing, to provide details of the expertise held by its inspector and members. That duty requires public bodies to disclose relevant material in judicial review proceedings, but it did not reverse the normal burden of proof.
Mr Justice Nolan said he had “serious doubts” about whether the Commission had the necessary expertise to address the groundwater and tufa issues. Nonetheless, Mr Rogers had not established a lack of expertise on an evidential basis and therefore had not met the threshold for the relief sought. The case was listed for mention on 11 May 2026.