Keele Research Repository

Ever since the Wednesbury decision in 1947 UK courts and UK public law scholars have been struggling to comprehend the meaning of ‘reasonableness’ and its relation to ‘proportionality’. The main purpose of this article is to promote conceptual clarity in UK public law by describing the nature of reasonableness and proportionality as grounds of judicial review and by highlighting the overlooked similarities and differences between them. The main arguments of this article are that (1) reasonableness is in its essence a balancing and weighing test; (2) proportionality adds very little to already existing grounds of judicial review in UK public law; (3) this addition is not necessarily focused on the administrative weighing and balancing process; and (4) since proportionality adds very little to already existing grounds of judicial review, no conceptual or normative reason prevents having proportionality as a general ground of judicial review in UK public law.