Put in another way, service is a precondition to the exercise of jurisdiction by the Courts. Where there is no service or there is a procedural fault in service in subsequent proceedings are a nullity ab initio. This is based on the principle of law that a party should know or be aware that there is a suit against him so that he can put up a defence. If after service, he does not put up a defence the law will assume and rightly too for that matter that he had no defence. Failure to serve process where service is required in a particular manner is a fundamental vice. It deprives the Court of the necessary competence and jurisdiction to hear the suit. That is to say, that the condition precedent to the exercise of jurisdiction was not fulfilled.
– S.C. OSEJI, J.S.C. Odey v. Alaga (2021) – SC.9/2021