(1) Subject to subsection (5), where in a review it appears to the reviewing authority:
(a) that the conviction is unreasonable, or cannot be supported, having regard to the evidence;
(b) that, as a result of a wrong decision on a question of law, or of mixed law and fact, the conviction was wrong in law and that a substantial miscarriage of justice has occurred;
(c) that there was a material irregularity in the course of the proceedings and that a substantial miscarriage of justice has occurred; or
(d) that, in all the circumstances of the case, the conviction is unsafe or unsatisfactory;
the reviewing authority shall quash the conviction.
(2) Subject to subsection (5), where in a review it appears to the reviewing authority that there is evidence that:
(a) was not reasonably available during the proceedings;
(b) is likely to be credible; and
(c) would have been admissible in the proceedings;
the reviewing authority shall receive and consider that evidence and, if the reviewing authority considers that the conviction cannot be supported having regard to that evidence, the reviewing authority shall quash the conviction.
(3) Subject to subsection (5), where in a review the reviewing authority is satisfied that, at the time of the act or omission the subject of the charge, the convicted person was suffering from such unsoundness of mind as not to be responsible, in accordance with law, for that act or omission, the reviewing authority shall:
(a) quash the conviction;
(b) substitute for the conviction so quashed an acquittal on the ground of unsoundness of mind; and
(c) direct that the person be kept in strict custody until the pleasure of the Governor - General is known.
(4) Where in a review it appears to the reviewing authority that the court martial or the Defence Force magistrate should have found that the convicted person, by reason of unsoundness of mind, was not able to understand the proceedings against him or her and accordingly was unfit to stand trial, the reviewing authority shall quash the conviction and direct that the person be kept in strict custody until the pleasure of the Governor - General is known.
(5) A reviewing authority shall not quash a conviction under subsection (3) or (4) if there are grounds for quashing the conviction under subsection (1) or (2).