“Appeal against finding of not guilty on ground of insanityS 12(1)A person in whose case a finding is recorded under Article 50(1) of the Mental Health Order that he was not guilty of the offence charged on the ground of insanity may appeal to the Court of Appeal against that finding  –(a)with the leave of the Court; or(b)if the judge of the court of trial grants a certificate that the case is fit for appeal.(2)Subject to subsection (4) below, the Court −(a)shall allow an appeal under this section if it thinks that the finding is unsafe; and(b)shall dismiss such an appeal in any other case.(4)Where but for this subsection –(a)an appeal under this section would fall to be allowed; and(b)none of the grounds for allowing it relates to the question of the insanity of the appellant,the Court may dismiss the appeal if of opinion that but for the insanity of the accused the proper verdict would have been that he was guilty of an offence other than the offence charged.Disposal of appeal allowed under s12S 13(1)The following provisions apply where an appeal under section 12 of this Act is allowed in accordance with that section.(2)If the ground, or one of the grounds, for allowing the appeal is that the finding of the jury as to the insanity of the accused ought not to stand, but the Court of Appeal is of opinion that the proper verdict would have been that he was guilty of an offence (whether the offence charged or any other offence of which the jury could have found him guilty), the Court –(a)shall substitute for the finding of not guilty on the ground of insanity a verdict of guilty of that offence; and(b)subject to subsection (3) below, shall have the like powers of punishing or otherwise dealing with the appellant and all other powers as the court of trial would have had if the jury had returned that verdict.(3)Where the offence mentioned in subsection (2) above is one for which the sentence fixed by law is one of death or of imprisonment for life, the sentence shall (whatever the circumstances) be one of imprisonment for life.(4)In a case where the Court allows an appeal under section 12 above but subsection (2) of this section does not apply, the Court shall substitute for the finding of the jury a verdict of acquittal.(5)An order of the Court allowing an appeal under section 12 of this Act shall operate as a direction to the chief clerk acting for the court of trial to amend the record to conform with the order.(5A)Where, on an appeal under section 12, the Court is of opinion that the case is not one where there should have been a verdict of acquittal but that there should have been findings that the accused was unfit to be tried and that he did the act or made the omission charged against him, the court may make any such order as may be made under Article 50A(2) of the Mental Health Order (powers to deal with persons found not guilty on the ground of insanity).(6)Where in accordance with subsection (4) of this section the Court substitutes a verdict of acquittal for a finding of not guilty on the ground of insanity, any order previously made in consequence of that finding under Article 50A(2) of the Mental Health Order shall cease to have effect, so however that if the Court is of opinion −(a)that the appellant is suffering from mental disorder of a nature or degree which warrants his detention in a hospital for assessment (or for assessment followed by medical treatment); and(b)that failure to so detain him would create a substantial likelihood of serious physical harm to himself or to other persons,the Court shall make an order that the appellant be admitted for assessment to such hospital as may be required by the Department of Health and Social Services; and Schedule 2 to this Act shall apply as to the consequences and effect of an order made by the Court under this subsection.”
Annex Extract from the Criminal Appeal (Northern Ireland) Act 1980: