PRINCIPLE STATEMENT

A proviso cannot enlarge or contract the scope of a clear enactment. It may guide selection between two possible constructions when doubt exists. But it cannot create an enacting provision enabling something not found in the enactment itself simply because otherwise the proviso would be meaningless.

RATIO DECIDENDI (SOURCE)

Per Onu, JSC, in Kotoye v. Saraki & Anor (1994) NLC-1471993(SC) at pp. 37–38; Paras E–A, citing Western Derby Union v. Metropolitan Life Assurance Society (1897) A.C. 647 at 655–656.
"I decline to read into any enactment words which are not to be found there, and which would alter its operative effect because of provisions to be found in any proviso. Of course a proviso may be used to guide you in the selection of one or other of two possible constructions of the words to be found in the enactment, and show when there is doubt about its scope, when it may reasonably admit of doubt as to its having this scope or that, which is the proper view to take of it; but to find in it an enacting provision which enables something to be done which is not to be found in the enactment itself on any reasonable construction of it, simply because otherwise the proviso would be meaningless and senseless, would, as I have said, be in the highest degree dangerous."
View Judgment

EXPLANATION / SCOPE

A proviso cannot enlarge or contract the scope of a clear enactment. It may resolve ambiguity by guiding selection between possible constructions. It cannot create substantive provisions not found in the main enactment. The principle applies to statutory interpretation. The rule prevents provisos from overriding clear legislative intent. A proviso cannot be used to rewrite or expand the enactment it qualifies.

CASES APPLYING THIS PRINCIPLE