Skip to main content

Recent High Court decision refining on Finney and S73 changes affecting operative wording

12 September 2023

On 6 September, the High Court handed down judgment in R (Fiske) v Test Valley Borough Council [2023] EWHC 2221 (Admin), to quash a decision granting planning permission pursuant to S73 TCPA 1990 for a solar farm development in the Test Valley.

Mr Justice Morris held that there are “two distinct restrictions” on the exercise of power under section 73. These are:

1. the S73 permission must not introduce a condition that “creates a conflict or is inconsistent” with the operative wording of the original planning permission and its conditions and;

2. the S73 permission must not “fundamentally alter” the development permitted by the original permission.

In reaching this decision the Judge relied heavily on Finney v Welsh Ministers [2020] PTSR 455 [2019] EWCA Civ 1868.

The Facts

In April 2022 the Claimant, Mrs Chala Fiske, applied for an order to quash a S73 planning permission (“the S73 Permission”) to vary conditions within an earlier planning permission granted in 2017 (“the Original Permission”). The Original Permission was for a ground mounted solar farm within 72 hectares of agricultural land at Woodington Farm, Woodington Road, East Wellow. The precise operative wording was:

Installation of a ground mounted solar park to include ancillary equipment, inverters, substation, perimeter fencing, cctv cameras, access tracks and associated landscaping.

Conditions 2 and 15 approved details for a 33kV substation. Subsequently, the S73 Permission was granted to allow various design changes to the scheme the effect of which was to remove the 33kV substation from the approved plans. The omission of the 33kV was not substantially disputed by the Council as they had relied upon the solar farm working in parallel with a separate planning permission for a DNO substation development that had been approved in May 2021 (Ref:20/00814/FULLS).


The Claimant argued that the S73 Permission was unlawful for two reasons:

1. The S73 Permission was ultra vires since removing the substation permitted by the Original Permission, the Council granted a permission that conflicted with the operative wording of the Original Permission and/or that fundamentally altered the development permitted under the Original Permission; and

2. The Council failed to have regard to a mandatory material consideration, namely the fact that in granting the 2022 Permission it would be granting a permission which altered the Original Permission by removal of the substation.

Legal Issues

Section 73 grants local planning authorities the power to make changes to planning conditions imposed under an existing permission. The question the Judge focused on in this instance was whether, as the Claimant argued, this power was restricted in two ways:

1. (conflict with operative part) and;

2. (fundamental alteration of the permission as a whole) - or, as the Defendant submitted, there was only a single restriction being restriction 2.

J Morris concluded that on the balance of case authorities, and in particular Finney, both restrictions 1 and 2 apply to the exercise of power under S73. He rejected the argument that there was only a single “fundamental alteration” test.

In his judgment, Condition 2 of the S73 Permission was inconsistent with and in conflict with the operative wording of the Original Permission because it effectively removed the ability to develop a substation as allowed for within the operative wording. For this reason, the S73 Permission was ultra vires. However, he went on to also analyse whether the removal constituted a fundamental alteration of the Original Permission. He concluded that as at the date of the Original Permission “the existence of the 33kV substation was a central part of the development” and that removing such a central element did amount to a fundamental alteration of the development.

For these reasons, Ground 1 was successful and the need to reach any conclusion on Ground 2 fell away.


This case highlights the need for care to be taken in relying on S73 to vary conditions that could conflict with operative wording. It also illustrates the importance of the proposed new S73B power to make “non-substantial” changes under the Levelling Up and Regeneration Bill. If passed, this will allow local authorities to amend both planning conditions and the description of a development so long as they are satisfied the changes will not be substantially different from the existing permission.

James Burton of 39 Essex Chambers and Lewis Silkin Planning Partner, Sara Hanrahan acted for the Claimant.

Read the full judgement here.

Related items

Back To Top