Except as provided by this section, an appellant shall be entitled to be present, if he wishes it, on the hearing of his appeal, although he may be in custody.
A person in custody shall not be entitled to be present—
where his appeal is on some ground involving a question of law alone; or
on an application by him for leave to appeal; or
on any proceedings preliminary or incidental to an appeal; or
where he is in custody in consequence of a verdict of not guilty by reason of insanity or of a finding of disability,
unless the Court of Appeal give him leave to be present.
The power of the Court of Appeal to pass sentence on a person may be exercised although he is for any reason not present.
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