15(1)
Where there has been a determination under section 4 of the Criminal Procedure (Insanity) Act 1964 of the question of a person's fitness to be tried, and there have been findings that he is under a disability and that he did the act or made the omission charged against him, the person may appeal to the Court of Appeal against either or both of those findings.
15(2)
An appeal under this section lies only—
(a) with the leave of the Court of Appeal; or
(b) if, within 28 days from the date of the finding that the accused did the act or made the omission charged, the judge of the court of trial grants a certificate that the case is fit for appeal.