Flenley & Anor, R (on the application of) v London Borough of Hammersmith & Fulham

In planning judicial review, a development plan includes both its policies and their reasoned justification. A guideline in the justification may therefore be a material consideration, even where it is not expressed as a mandatory rule. Where a proposal substantially departs from an important guideline relevant to neighbouring amenity, the decision-maker should address the departure and explain why the guideline is not followed. A failure to do so may establish failure to take a material consideration into account. Reasons supplied after proceedings begin require particular caution, especially where they differ from the contemporaneous documents. The decision should be quashed where there is a real possibility that a properly informed decision-maker would reach a different conclusion.

The claimants, neighbouring residential occupiers, sought judicial review of planning permission granted by the defendant council for a two-storey rear extension. They argued that the council had failed to consider paragraph 4.82 of its Unitary Development Plan, which stated that rear extensions should comprise no more than half the width of the property. The proposed extension covered about 80 per cent of the existing building’s width.

The permission had been granted under delegated powers. The central issues were whether the width guideline was a material consideration, whether it had been taken into account, and whether the court should nevertheless decline to quash the permission because the outcome would have been the same.

1. Claim succeeded. The planning permission was quashed. The defendant was ordered to pay the claimants’ costs of £4,083.76. Permission to appeal was refused.
2. Under section 38(6) of the Planning and Compulsory Purchase Act 2004 and section 70 of the Town and Country Planning Act 1990, the determination had to accord with the development plan unless material considerations indicated otherwise. The development plan comprised both the relevant policies and their reasoned justification. Although the policies were of primary importance, the justification informed their application and could itself constitute a material consideration.
3. The statement in paragraph 4.82 that extensions should comprise no more than half the width of the rear property was a guideline, not a mandatory requirement. However, because the proposed extension occupied about 80 per cent of the width and width was an important consideration in assessing neighbouring amenity, the officer’s report should have addressed the departure and explained why the guideline was not followed.
4. The report dealt expressly with the excessive depth of the extension but did not address its excessive width. The planning permission and the council’s pre-action response were similarly silent. Those contemporaneous materials indicated that the width issue had not been considered.
5. The later witness statements of the planning officers were given no significant weight. Applying the caution identified in R (D) v the Secretary of State for the Home Department [2003] EWHC 155 and Nash v Chelsea College of Art and Design (2001) EWHC Admin 538, the court considered that the statements risked ex post facto rationalisation and did not specifically establish consideration of the width guideline.
6. The applicable question was whether there was a real possibility that the council would reach a different conclusion if it considered the width issue, applying Metropolitan Borough Council v the Secretary of State for the Environment and Greater Manchester Waste Disposal Authority 61 P&CR 343. That possibility existed. A fresh decision should preferably be made by a different decision-maker, potentially by members rather than under delegated powers, after interested parties had an opportunity to make further representations.