High Court on highway widths

In Wilkins v Secretary of State for Environment, Food, and Rural Affairs [2025] EWHC 2435 (Admin) the High Court has handed down judgment dismissing a challenge to an inspector’s decision to confirm a Definitive Map Modification Order (the Kent County Council (Restricted Byway AB27 at Tenterden) Definitive Map Modification Order 2021).

The background to the litigation was a dispute between the owners of the Morghew Park Estate and Morghew Park House. The route at the centre of the dispute was originally recorded as a road used as a public path, and following the enactment of the Natural England and Rural Communities Act 2006, was reclassified as a restricted byway.

The Claimants (who owned Morghew Park House, near which the route passes) had made a series of applications for modifications to the Definitive Map. The third of those modifications sought to add widths to the definitive statement, and it was that application with which the litigation was concerned.

The order making authority, Kent County Council, had determined that the width of the route should be scaled off the Ordinance Survey Maps. The Claimants objected to that decision, which was essentially upheld by the Secretary of State, with the Inspector holding that it was appropriate and necessary to define the width of the Order route with reference to the 25 Inch Third Edition OS Map.

The Claimants challenged that decision on three grounds, namely: (1) That the Inspector had misdirected himself as to the correct legal test, and in particular had wrongly relied upon the boundary-to-boundary principle; (2) That the Inspector had unlawfully departed from a previous inspector’s decision; and (3) That reliance upon the OS Maps was irrational. In support of those grounds the Claimants relied upon a witness statement from Robin Carr, an expert in highways and rights of way.

The High Court dismissed the claim holding as follows:

First, large portions of Mr Carr’s evidence, to which the Secretary of State had objected, were argumentative and crossed the line into inadmissible expert opinion. They were not before the Inspector and fell to be excluded (paras. 54-57).

Second, the Inspector had not misdirected himself as to the boundary-to-boundary principle. Rather, reading the decision fairly, the Inspector had applied the test for dedication and had found evidence of actual use by the public across the whole width between the relevant boundary features (paras. 66-89).

Third, notwithstanding the Claimants’ reliance upon R (Sears Group Properties Ltd) v Cardiff CC [1998] PLCR 262 to suggest that where a decision made by a competent authority on a particular issue affecting private rights will be binding on other authorities directly involved unless and until circumstances change that can reasonably be found to undermine the basis of the original decision, the previous inspector’s decision was not binding and was in any event directed at a different question and different issues, such that there was no true disagreement or inconsistency.

Finally, the Inspector had acknowledged the potential issues with the accuracy of the OS mapping, but had concluded that the OS Maps would be significantly more accurate than alleged by the Claimants. He was entitled to rely upon the excellent reputation of the OS and to conclude that the Maps represented the best evidence as to the width of the route such that scaling from them was appropriate.

For those reasons, the claim was dismissed on all grounds.

Charles Streeten is a barrister at Francis Taylor Building. He acted for the successful Defendant, the Secretary of State for Environment, Food, and Rural Affairs, instructed by the Government Legal Department.