There are two ways in which fresh evidence may become admissible on appeal:
(1) Dixon Test: On the basis of non-disclosure giving rise to a breach of the right to make full answer and defence. This is governed by the test first set out in Dixon, (the “Dixon test”); or
(2) Palmer Test: On the basis that the cogency of the evidence is such that it warrants admission and the interests of justice require that it be received. This is governed by the test first set out in R. v. Palmer,  1 S.C.R. 759 (the “Palmer test“)..
The Dixon Test
There are two components to the Dixon test.
1. Did the Crown breach its duty to disclose?
If the court concludes that, at the relevant time, the Crown failed in its disclosure obligations, then Dixon requires that the court go on to consider the following:
2. Was there a “reasonable possibility” that the non-disclosure:
(a) impacted the outcome of the trial; or
(b) impacted the overall fairness of the trial process?
R. v. Taillefer, 2003 SCC 70,  3 S.C.R. 307, at paras. 71, 78;
See also Dixon, R. v. Dixon, 1998 CanLII 805 (SCC), at paras. 34-35.
Although, a reasonable possibility must be more than “entirely speculative” in nature, the mere existence of such a possibility constitutes an infringement of the right to make full answer and defence: Taillefer, at para. 78.