However, Lord Justice Sullivan accepted that, at the moment, the Government's intention may only be worthy of being given weight in "very few" of the cases in which the proposed abolition of regional strategies will be relevant.
The court found that two indeterminate legal obstacles - the need for Parliament’s acceptance of the proposal and the requirement to undertake strategic environmental assessments for the revocation of each strategy - would often make it inappropriate for decision-makers to at this stage give significant weight to the Government's intention on RSSs.
But the judge considered that there were finely-balanced cases in which it would be appropriate to assign that weight. He cited the example of a large strategic site being developed over 15 to 20 years, where housing numbers provided the only argument in favour of the development, in the face of strong site-specific objections.
But in cases such as that, the court said, it would be necessary to give "very clear and cogent reasons" for the exception, on account of the indeterminate outcome of the parliamentary and SEA process.
Ian Ginbey, head of planning at law firm Clyde & Co, which acted for CALA, said: "This is an important decision which fully vindicates CALA's action in challenging the government's approach, and seeking to restore clarity to the planning system."
The Communities & Local Government department was invited by Planning to comment, but at the time of writing had not responded.
On 10 November 2010, the High Court ruled that the secretary of state’s revocation of regional strategies in July last year was unlawful.
However, the secretary of state and the Government’s chief planner Steve Quartermain immediately issued guidance insisting that, notwithstanding the illegality of revocation, decision makers should still have regard to the Government's intention to rapidly abolish regional strategies as a material consideration.
CALA challenged this, but following a series of court hearings was eventually defeated in February when the High Court ruled that councils should regard the letter as material consideration.
CALA then appealed against this decision, leading to today’s decision.
In addition, the court said that local planning authorities would be acting unlawfully if they took the intention to revoke into consideration when drawing up their plans.
A host of councils across the country rushed to reduce housing numbers in their development plans following Eric Pickle’s invitation to them, in letters dated 27 May and 10 November 2010, to take his intention to scrap regional strategies into account in decisions.
Ginbey said: "Without this highly significant finding, many decision-makers appear to have been led into error in attaching undue weight to the Government’s intention to revoke."
Research by planning consultant Tetlow King estimates that councils across England have announced intentions to scrap up to 221,000 homes in the wake of the decision.
Bristol City Council revised its emerging core strategy to reduce planned housing numbers after the publication of Pickles' letters, but subsequently removed references in its document to the secretary of state's declared intention. The strategy has been approved by an inspector and is awaiting a vote on formal adoption.
Other councils, including Bath and North East Somerset and South Gloucestershire, have drawn up revised targets and are awaiting the opening of inquiries into them, while others are consulting on lower figures.
But Jamie Sullivan, senior planner at Tetlow King said: "It is quite contentious to do so, but some councils have been working on the basis of their revised figures even before they have been formally adopted."
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