Sainsbury's Supermarkets Ltd, R (on the application of) v First Secretary of State & Anor

In assessing quantitative retail need under PPG6 and related ministerial guidance, a decision-maker must consider all evidence capable of bearing on that issue. Evidence primarily relied on for another purpose may be relevant, including evidence of overtrading and the absence of adverse impact on nearby town centres. Overtrading is not, by itself, proof of quantitative need, but its significance depends on the circumstances. A decision-maker who rejects an accepted evidential methodology must explain why, particularly where expert evidence supports it. A failure to consider material evidence, together with inadequate reasons, is an error of law requiring the decision to be quashed.

The claimant sought under section 288 of the Town and Country Planning Act 1990 to quash the Secretary of State’s refusal of planning permission for a substantial extension to an out-of-centre supermarket at Kidlington. The local authority had resolved to grant permission, and an inspector recommended permission after a public inquiry. The Secretary of State accepted the inspector’s findings on the sequential approach, qualitative need and retail impact, but rejected the conclusion that quantitative need had been established. The central issues were whether overtrading could be relevant to quantitative need, whether the Secretary of State had adequately explained his rejection of the claimant’s methodology, and whether the decision mischaracterised the policy objective.

1. Claim allowed. The Secretary of State’s decision was quashed for errors of law. The claimant obtained an order for costs of £18,500.
2. Under the relevant PPG6 guidance and the McNulty Statement, quantitative need required separate consideration. That did not mean that only evidence directly advanced as proof of quantitative need could be considered. The decision-maker had to take into account all relevant evidence capable of bearing on that question.
3. Overtrading could be an indicator of quantitative need, although its weight depended on the circumstances. In this case, the store’s substantial overtrading, evidence of congestion and cramped conditions, the absence of evidence that its location attracted significant trade from outside the catchment area, and the absence of adverse impact on nearby centres were relevant considerations. The Secretary of State erred by treating overtrading as incapable of indicating quantitative need and by failing to consider the surrounding circumstances.
4. The Secretary of State also gave inadequate and factually erroneous reasons for rejecting the quantitative-need assessment. Where competing experts accepted the methodology as appropriate and reasonable, the decision-maker was not bound to accept their opinions, but had to explain why the methodology or its assumptions were rejected. The reasoning did not make the basis of rejection intelligible or enable the claimant to understand what evidence or method would have been required.
5. The statement that failure to demonstrate quantitative need was contrary to a key objective of PPG6 was inaccurate. The principal objective was to protect and enhance the vitality and viability of town centres. That error alone would not have justified relief, but it supported the conclusion that quantitative need had been treated in isolation.