Council seeks judicial review in dispute over finding of planning inspector on duty to cooperate

Mid Sussex District Council has launched a judicial review against the Secretary of State for Housing, Communities and Local Government in a row about a planning inspector's finding that the council's local development plan failed to meet the duty to cooperate.

The council has said it is "astonished that the inspector's conclusions are one which the Secretary of State would even want to defend", arguing that rejecting the plan could delay thousands of new homes.

Mid Sussex's district plan, which covers the years 2021 - 2039, reached the examination stage last year and was subject to a series of hearings hosted by a planning inspector in October 2024.

In a letter following the hearings, issued in April 2025, the inspector said that Mid Sussex had failed to show that it had engaged "constructively, in an active and ongoing way" to help neighbouring councils meet "significant" unmet housing needs.

Her letter added: "The failure here is that the council has not adequately considered the requests of its neighbours – namely Crawley, Horsham and Brighton and Hove, in a constructive, active and ongoing way."

The inspector said the local authority could either withdraw the plan from examination or ask that the inspector write a report of her conclusions.

"I should say that the latter would involve further expense, and that the contents of the report would likely be very similar to this letter," she added.

In its ensuing pre-action protocol letter dated 17 April, the council said the inspector's letter "entirely fails to grapple with the council's case that the approach it has taken has in fact maximised the amount of housing which can be delivered without an 'adverse impact when assessed against policies in the Framework'".

The letter also said the inspector failed "to explain what the council could possibly have done to make the Plan more effective in addressing the unmet needs of adjoining areas".

The council highlighted previous successes in meeting housing need, including 1,498 additional dwellings to meet the unmet needs of neighbouring authorities in its Mid-Sussex District Plan 2014-2031 and the delivery of more than 1,000 new homes a year since adopting its 2014 - 2031 development plan, in excess of Mid Sussex's housing delivery target.

"In the council's view, this track record (of both taking the issue of meeting housing needs seriously and demonstrable over-delivery in meeting that need) has been exemplary," the letter said.

"Critically, it is a record which is reflected in, and would be continued under the Plan, which (as stated above) would not only meet all of Mid-Sussex's own needs, but would also provide an additional 1,042 homes to meet the needs of surrounding areas."

The council warned that rejecting the plan would mean the loss of a "ready to go" local plan that could allocate more than 8,000 new homes and would waste taxpayers' money and cause several years' worth of delays in delivering a new plan.

"The council finds it impossible to understand how that outcome is consistent either with the plan-led system, or the Government's commitment to delivering 1.5 million new homes over the next five years," the letter added.

However, MHCLG later said it did not agree with the council's reasoning and said it agreed with the inspector that it is necessary for the plan to identify the beneficiaries of the council's surplus of homes.

Responding to the Ministry in a letter dated 2 June, the council said its response "fails to grapple with a number of key points" and later added: "The council is astonished that the Inspector's conclusions are one which the Secretary of State would even want to defend."

The council said a "far simpler solution" to the disagreement would involve the inspector recommending a main modification to the plan.

The Leader of Mid Sussex District Council, Cllr Robert Eggleston said:  "Mid Sussex has drawn up its plan following the advice of very senior planning lawyers and advisors, so we are understandably amazed at the Inspector's rationale. 

"It is extraordinary that the inspector has ignored the evidence we provided. The same evidence that has previously satisfied other Inspectors."

Cllr Eggleston added: "We are left with no choice. We must protect Mid Sussex from unplanned, speculative development.

"We have worked diligently for many years to undertake the work thoroughly and in accordance with government guidance and the law. The inspector's ill-founded conclusions are a slap in the face for proper plan making and the patient, careful work needed to build consensus amongst communities and with our partners."

A spokesperson for the Ministry for Housing, Communities and Local Government said it would not be appropriate for the department to comment on the litigation at this time.

Adam Carey