In R (MAS) v SoS for DEFRA (2019) EWHC 158 (Admin), Morris J, at paragraphs 53/54, stated the principles of proportionality as follows:-
(1) Proportionality is a general principle of EU law;
(2) Its application in any particular case is always highly fact-sensitive;
(3) It applies to national measures falling within the scope of EU law;
(4) It applies only to measures interfering with protected interests;
(5) Protected interests include the fundamental freedoms governed by the EU Treaties;
(6) Where the issue is the validity of a national measure, it is for the national Court to reach its own conclusion on proportionality;
(7) It is not merely a review of the proportionality assessment of the national authority responsible for the measure;
(8) Proportionality involves the consideration of (at least) two questions –
(i) whether the measure in question is appropriate or suitable to achieve the objective pursued, and
(ii) whether the measure is necessary to achieve that objective, or whether it could be attained by a less onerous method;
(9) However, this does not require the selection of the least onerous method;
(10) Rather, the question is whether a less onerous method could have been used without unacceptably compromising the objective pursued;
(11) Further, there is some debate as to whether there is a third question: whether the burden imposed by the measure is disproportionate to the benefits secured.
Morris J also, at paragraphs 56/57, stated the overlapping principles as to fettering of discretion and the adoption of a policy as follows:-
(1) A person upon whom a discretionary power has been conferred –
(i) must exercise it on each occasion in the light of the circumstances at the time,
(ii) cannot fetter its exercise in the future by committing now as to the way in which it will be exercised in the future,
(iii) cannot fetter its future exercise by ruling out of consideration factors which may then be relevant,
(iv) may nevertheless develop and apply a policy as to the approach to be adopted in the generality of cases,
(v) must not preclude departure from the policy, and
(vi) must not preclude taking into account circumstances which are relevant to the particular case;
(2) If an inflexible and invariable policy is adopted, both the policy and the decisions taken pursuant to it will be unlawful;
(3) The exercise of public discretionary power requires the decision maker to bring its mind to bear on every case;
(4) A pre-existing policy must not be blindly followed;
(5) However, a policy maker is entitled to express policy in unqualified terms;
(6) The policy maker is not required to spell out the legal fact that the application of policy must allow for the possibility of exceptions;
(7) A general policy that does not, on its face, permit of exceptions, will be permitted in most circumstances;
(8) The proof of unlawful fettering of discretion will be in lack of willingness to consider exceptions to the policy, rather than in the policy wording itself not acknowledging the potential for exceptions;
(9) There is no requirement for a policy expressly to state that it must be applied consistently with the rule against fettering discretion;
(10) A policy may, but need not, incorporate exceptions as a part of the policy;
(11) Policy is no less and no more than a guide to the exercise of discretion: it is not a rule, and it is subject to something new that is said.