of his two year old half brother, Osazuwamen, an offence punishable under section 319(1) of the Criminal Code, Cap. 48, Vol. II Laws of Bendel State of Nigeria, 1976. At the trial in which six witnesses testified for the prosecution, the fact that the act of the appellant caused the death of the deceased was not contested. Indeed, both in his statement to the police exhibit B and his evidence in court, the appellant confessed to killing the deceased. What was canvassed on his behalf was the defence of insanity. But the learned trial Judge, Obi J., in his judgment of 29th July, 1988 exhaustively considered that defence and in rejecting it, he convicted the appellant of murder and passed a death sentence on him. On appeal by the appellant to the Benin division of the Court of Appeal, the main plank of the appeal was that the learned trial Judge ought to have conducted an inquiry to ascertain the actual age of the appellant at the time the offence was committed since if he was found to be under 17 years of age, an appropriate sentence would have been for his imprisonment at the pleasure of the Governor. The Court of Appeal in dismissing the appeal held that no issue about the appellant's age arose during the trial of the appellant in the High Court to warrant an enquiry before that court as to the actual age of the appellant at the time of the commission of the offence. In his further appeal to this court, the appellant by his counsel identified two issues for determination in his brief of argument. These are: "1. Whether the defence of insanity did not avail the appellant. 2. Whether the Court of Appeal was right in not holding that there was sufficient material at the trial court to have justified an inquiry by the Judge into the actual age of the appellant at the time of the commission of the offence." In the respondent's brief of argument, similar issues were raised, to wit: "1. Whether the defence of insanity will avail the appellant having regard to the state of the overwhelming evidence before the court. 2. Whether it was right of the Appeal Court to hold that an inquiry into the age of the appellant was not necessary not being an issue before the court." Dealing with the first issue for determination, learned counsel for the appellant in his brief of argument referred to the evidence of P.W.2, the step mother of the appellant and mother of the deceased who testified that she had no quarrel with the appellant before the incident; he also referred to the evidence of P.W.3 the father of the appellant who in cross-examination stated that the appellant had mental problems in respect of which he was treated by a native doctor without any improvement when he, P.W.3 resorted to treating him at home. Attention was also drawn to the evidence of the investigating police officer (P.W.6) who testified that at the time he was recording the statement of the appellant, he, the appellant was behaving abnormally. Reference was also made to the evidence of the appellant to the effect that in the morning of the incident, he was having headache and pains in his ears. It was then submitted that these pieces of evidence from P.W.2, P.W.3, P.W.6 and the appellant himself establish that the appellant was insane at the material time. It was further submitted that where there exists some evidence pointing towards insanity or abnormal behaviour, then the lack of motive for the offence which ordinarily is of no moment becomes a relevant consideration in deciding whether the appellant was insane at the material time of the offence. For this proposition, counsel referred to the following cases: Onyekwe v. The State (1988) 1