AC-2024-LON-001142 - [2025] EWHC 2015 (Admin)

The present claim also includes a rationality challenge as to outcome. This gives rise to the question whether – even if the process of reasoning leading to the challenged decision is not materially flawed – the outcome is “so unreasonable that no reasonable authority could ever have come to it” (Associated Wednesbury Picture Houses Ltd v Wednesbury Corporation  [1948] 1 KB 223, 233-4), or, as the test is often put in more recent cases, is outside the “range of reasonable decisions open to the decision-maker” in those circumstances (Boddington v BTP  [1999] 2 AC 143, at p 175).

Ordinary judicial review principles allow a court “to determine whether [the regulator’s] conclusions are adequately supported by evidence, that the facts have been properly found, that all material factual considerations have been taken into account, and that material facts have not been omitted”; Unichem v Office for Fair Trading [2005] CAT 8, [2005] 2 All ER 400 at paragraph [174], and, therefore, to inquire whether there was adequate material to support the decision reached; see per Carnwath LJ at paragraph [93] IBA Healthcare Ltd v Office of Fair Trading [2004] EWCA Civ 142.