Nothing in this Act shall affect the prerogative of mercy, but the Secretary for Scotland on the consideration of any petition for the exercise of His Majesty's mercy, having reference to the conviction of a person on indictment or to the sentence (other than sentence of death) passed on a person who has been so convicted, may, if he thinks fit, at any time, and whether an appeal or an application for leave to appeal against such conviction or sentence has or has not previously been heard and determined by the Court, either—
(a)refer the whole case to the Court and the case shall then be heard and determined by the Court as in the case of an appeal under this Act; or
(b)if he desires the assistance of the Court on any point arising in the case with a view to the determination of the petition, refer that point to the Court for their opinion thereon, and the Court shall consider the point so referred and furnish the Secretary for Scotland with their opinion thereon accordingly.