How different is proportionality in the EU context from proportionality in other contexts?

The Legal Services Board, tasked with the supervision of approved regulators of persons carrying on legal activities, granted an application (by the Bar Standards Board, Solicitors Regulation Authority, and ILEX Professional Standards Board) for approval of alterations to their regulatory arrangements to give effect to the so-called Quality Assurance Scheme for Advocates (“the decision”). The Scheme provides for judicial assessment of criminal advocates in England and Wales: only those deemed “competent” would gain full accreditation for upper levels of criminal work. Judicial review had been sought, unsuccessfully in the courts below, by barristers practising criminal law. The question in R. (on the application of Lumsdon and others) v Legal Services Board [2015] UKSC 41; [2015] 3 W.L.R. 121 was whether the decision was contrary to Regulation 14 of the Provision of Service Regulations 2009 (SI 2999/2009), which implemented Directive 2006/123/EC (O.J. No. L 376, p. 36). Regulation 14 requires that any authorisation scheme cannot be set unless, inter alia, the need for such a scheme is “justified by an overriding reason relating to the public interest” and the scheme's objective “cannot be attained by means of a less restrictive measure” (see Regulation 14(2)).