Section 20: Powers of Court of Appeal in special cases

(1) If it appears to the Court of Appeal that an appellant, though not properly convicted on some count or part of the information or charge, has been properly convicted on some other count or part of the information or charge, the Court of Appeal may either affirm the sentence passed appellant at the trial, or pass such sentence in substitution therefor as it thinks proper, and as may be warranted in law by the verdict on the count or part of the information or charge on which the Court of Appeal considers that the appellant has been properly convicted.
(2) Where an appellant has been convicted of and the court which tried him could on the information or charge have found him guilty of some other offence, and on the finding of the trial court, it appears to the Court of Appeal that that court must have been satisfied of facts which proved him guilty of that other offence, the Court of A instead of allowing or dismissing the appeal, substitute for the verdict found by such court, a verdict of guilty of that offence and pass such sentence in substitution for the sentence passed at the trial as may be warranted in law for that other offence, not being a sentence of greater severity.
(3) If on any appeal it appears to the Court of Appeal that, although the appellant was guilty of the act or omission charged against him, he was insane at the time the act was done or omission made so as not to be responsible according to law for his action, the Court of Appeal may quash the sentence passed at the trial and order the appellant to be kept in custody as a person of unsound mind in such place and in such manner as the Court of Appeal may direct pleasure of the President of the Federal Republic, be known, and the President of the Federal Republic of Nigeria may thereupon and from time to time, give such order for the safe custody of the appellant during pleasure in such place and in such manner as the President of the Federal Republic of Nigeria may see fit.