Bronwen Manby, R (on the application of) v The Mayor and Burgesses of the London Borough of Hackney

An SPD may supply a material planning consideration, but its guidance is not part of the statutory development plan and does not create a presumption against permission. A planning authority that recognises relevant guidance must assess how it bears on the decision; merely mentioning it is not enough. A decision may be unlawful where an officer report reaches an amenity conclusion without applying the guide or explaining its effect. The same omission may amount to process irrationality, breach of the duty of reasonable inquiry and inadequate reasons. The bar on relief under the Senior Courts Act 1981 applies only where it is highly likely that the outcome would not have been substantially different absent the error. The court must not reach that conclusion by disregarding relevant evidence or substituting its own planning judgment.

A neighbour challenged Hackney’s grant of planning permission for extensions to the adjoining property. The permitted claim focused on the Council’s treatment of a 45-degree guide in its Residential Extensions and Alterations Supplementary Planning Document. The officer report referred to the guide but did not determine whether the proposal complied with it in relation to the claimant’s property. The case officer later confirmed that she had formed no view on compliance. The claimant relied on a post-decision drawing showing an alleged infringement, whose accuracy was not disputed.

The court considered whether the Council had been required to assess the guide and its amenity impact, whether the omission made the decision unlawful, and whether the statutory bar on relief prevented the decision from being quashed.

Claim allowed; planning permission quashed. The 45-degree rule in the SPD was guidance, not a development-plan criterion or a presumption against permission. Policy LP17 required the authority to have regard to the SPD, while section 38(6) of the Planning and Compulsory Purchase Act 2004 applied to the development plan. The rule was nevertheless a material consideration under section 70(2)(c) of the Town and Country Planning Act 1990. The authority retained responsibility for weight and planning judgment, but it had to assess how the guide bore on the application.

The court applied the material-consideration approach in R (ClientEarth) v Secretary of State for Business, Energy and Industrial Strategy [2020] EWHC 1303 (Admin). A token reference to a consideration does not amount to having regard to it. Here, the report cited the guide and concluded that neighbouring amenity would not be harmed, but the case officer had not identified the relevant window in No. 89 or formed any view on compliance. The claimant had raised the issue before the decision. The later drawing could not properly be ignored: its accuracy had not been disputed, and it supported the claimant’s case that the guide was infringed.

The omission also made the decision irrational in process, breached the Tameside duty to take reasonable steps to obtain relevant information, and left the reasons inadequate. The report was signed by both the case officer and her team leader, and its reasons were theirs; the court made no assumption that the team leader had separately weighed the matter. It distinguished Gill v London Borough of Brent [2021] EWHC 67 (Admin), where the guidance was less precise and had not been raised before the decision, and Hughes v Kirklees [2026] EWCA Civ 308, which concerned a decision reached on officers’ recommendations.

The high threshold in section 31(2A) of the Senior Courts Act 1981 was not met. The court could not find it highly likely that the outcome would have been substantially the same without the error while disregarding the drawing or making its own planning judgment. The decision was unlawful and was quashed.

On 14 January 2026, a deputy High Court judge granted permission to proceed on Ground 1 and refused permission on the other grounds.