In ADESOLA V. ABIDOYE (1999) 14 NWLR (Pt. 637) 28 @ p. 56, where the Supreme Court per Karibi-Whyte J.S.C., “The construction of the word “may” in provisions of statutes has always raised difficulties. This is not because of the impression of the word … because the word “may” assumes a technical meaning depending upon the intendment of the statutory provision in which it is used. Although the etymological meaning of “may” is permissive and facultative and seldom can mean “must” and imperative it assumes this last-mentioned character; when there is anything in the provision that makes it the duty on the person on whom the power is conferred to exercise that power. When the exercise of the power is coupled with a duty on the person to whom it is given to exercise it, then it is imperative. In the instant case, there is a duty on the aggrieved who desires to set aside the decision of the prescribed authority to make his representation to the Commissioner for Chieftaincy Affairs within twenty-one days of the decision. The use of the expression ‘may’ in this situation is not merely facultative, but mandatory. There is no alternative.The aggrieved has no choice of action in the remedy provided for him….Accordingly, the word ‘may’ in Section 22(5) of the Chiefs Law of Oyo State, 1978 should be construed as imperative; the exercise of the right not being optional.”
It is a fundamental and cardinal principle of interpretation of statutes that where in its ordinary meaning a provision is clear and unambiguous, effect should be given to it without resorting to external aid. See A.-G., Federation v. A.-G., Abia State & Ors. (No.2) (2002) 6 NWLR (Pt. 764) 542 at 794 paras. B – C per Uwais CJN; A-G., Bendel State v. A.-G., Federation (1983) 1 SCNLR 239.
— M. Peter-Odili, JCA. CAC v. Ayedun (2005) – CA/A/152/2004