Dartford Borough Council v Secretary of State for Communities and Local Government & Anor

In a planning challenge, an inspector must address the applicable policy definition of a windfall site where that issue is material. A site which is not previously developed cannot be treated as a windfall site within the meaning of the relevant PPS3 footnote. An absence of a compelling case that development would be unsustainable is not itself a reason to grant permission or depart from a local policy requiring previously developed land. Where an irrelevant consideration has influenced the decision, the court should quash it unless satisfied that the same result would inevitably have followed on valid grounds.

The claimant challenged, under section 288 of the Town and Country Planning Act 1990, the Secretary of State’s decision to grant outline planning permission for the demolition of two bungalows and construction of eight houses. A planning inspector had allowed the interested party’s appeal under section 78 after the claimant refused permission. The challenge concerned the inspector’s treatment of the site as a possible windfall site and the weight given to unadopted Local Plan Review Policy H4, which required windfall sites to be previously developed land. The central issues were whether the inspector had misunderstood PPS3, relied on irrelevant considerations, and failed adequately to explain his departure from Policy H4.

1. The claim succeeded. The inspector’s decision was quashed. The court upheld both grounds of challenge.
2. The phrase “windfall site” in the context of PPS3 naturally bore the meaning stated in footnote 31 to paragraph 59: a previously developed site which had unexpectedly become available. The appeal site was not previously developed. The inspector therefore failed to take into account a relevant consideration when treating it as an appropriate windfall site.
3. The inspector gave insufficient and obscure reasons for attaching little weight to Policy H4. Its non-adoption could justify reduced weight, but the asserted inconsistency between Policy H4 and the amended PPS3 was unexplained. The 2010 amendments excluding private residential gardens from previously developed land appeared, if anything, more likely to discourage development on the site.
4. The inspector’s references to the gardens being large and not intensively used, and to earlier planning permission under different policies, did not explain why the current proposal should depart from Policy H4. There was no presumption in favour of development. The absence of a compelling case that the location was unsustainable could not itself justify permission or departure from a policy requiring previously developed land.
5. Applying the approach in Simplex GE (Holdings) Ltd v Secretary of State for the Environment [1988] 3 PLR 25, the court asked whether it was clear that the same decision would have been reached without the errors and irrelevant considerations. It was impossible to identify valid reasons pointing towards, or justifying, permission. The decision was accordingly quashed.

The claimant challenged the Secretary of State’s decision following a planning appeal. The judgment does not provide a reported citation for the inspector’s decision.

• Planning Inspector: allowed the appeal and granted outline planning permission.
• High Court (Administrative Court): upheld both grounds and quashed the Secretary of State’s decision.