A party in a criminal proceeding may seek to rely upon an out of court statement for the truth of its contents (also called hearsay) by demonstrating, on a balance of probabilities, that the admission of the statement is both necessary and sufficiently reliable (R. v. Khelawon, 2006 SCC 57 at para. 47).
The Supreme Court of Canada in R. v. Bradshaw,  1 S.C.R. 865 provides guidance with respect to assessing whether an out of court statement is sufficiently reliable to be admitted at trial. Karakatsanis, J., speaking for a majority of the Court, states at para. 26:
To determine whether a hearsay statement is admissible, the trial judge assesses the statement's threshold reliability. Threshold reliability is established when the hearsay "is sufficiently reliable to overcome the dangers arising from the difficulty of testing it" (Khelawon, at para. 49). These dangers arise notably due to the absence of contemporaneous cross-examination of the hearsay declarant before the trier of fact (Khelawon, at paras. 35 and 48). …The dangers relate to the difficulties of assessing the declarant's perception, memory, narration, or sincerity, and should be defined with precision to permit a realistic evaluation of whether they have been overcome.
At para. 27 Karakatsanis, J. outlines two pathways for establishing threshold reliability:
The hearsay dangers can be overcome and threshold reliability can be established by showing that (1) there are adequate substitutes for testing truth and accuracy (procedural reliability) or (2) there are sufficient circumstantial or evidentiary guarantees that the statement is inherently trustworthy (substantive reliability) (Khelawon, at paras. 61-63; Youvarajah, at para. 30).
With respect to procedural reliability, Karakatsanis, J. states at para. 28:
Procedural reliability is established when "there are adequate substitutes for testing the evidence", given that the declarant has not "state[d] the evidence in court, under oath, and under the scrutiny of contemporaneous cross-examination" (Khelawon, at para. 63). These substitutes must provide a satisfactory basis for the trier of fact to rationally evaluate the truth and accuracy of the hearsay statement (Khelawon, at para. 76; Hawkins, at para. 75; Youvarajah, at para. 36). Substitutes for traditional safeguards include a video recording of the statement, the presence of an oath, and a warning about the consequences of lying (B. (K.G.), at pp. 795-96). However, some form of cross-examination of the declarant, such as preliminary inquiry testimony (Hawkins) or cross-examination of a recanting witness at trial (B. (K.G.); R. v. U. (F.J.),  3 S.C.R. 764), is usually required (R. v. Couture, 2007 SCC 28,  2 S.C.R. 517, at paras. 92 and 95). …
With respect to substantive reliability, Karakatsanis, J. states at para. 30 that:
A hearsay statement is also admissible if substantive reliability is established, that is, if the statement is inherently trustworthy (Youvarajah, at para. 30; R. v. Smith,  2 S.C.R. 915, at p. 929). To determine whether the statement is inherently trustworthy, the trial judge can consider the circumstances in which it was made and evidence (if any) that corroborates or conflicts with the statement (Khelawon, at paras. 4, 62 and 94-100; R. v. Blackman, 2008 SCC 37,  2 S.C.R. 298, at para. 55).
Karakatsanis, J. continues at para. 31:
While the standard for substantive reliability is high, guarantee "as the word is used in the phrase 'circumstantial guarantee of trustworthiness', does not require that reliability be established with absolute certainty" (Smith, at p. 930). Rather, the trial judge must be satisfied that the statement is "so reliable that contemporaneous cross-examination of the declarant would add little if anything to the process"(Khelawon, at para. 49). The level of certainty required has been articulated in different ways throughout this Court's jurisprudence. Substantive reliability is established when the statement "is made under circumstances which substantially negate the possibility that the declarant was untruthful or mistaken" (Smith, at p. 933); "under such circumstances that even a sceptical caution would look upon it as trustworthy" (Khelawon, at para. 62, citing Wigmore, at p. 154); when the statement is so reliable that it is "unlikely to change under cross-examination" (Khelawon, at para. 107; Smith, at p. 937); when "there is no real concern about whether the statement is true or not because of the circumstances in which it came about" (Khelawon, at para. 62); when the only likely explanation is that the statement is true (U. (F.J.), at para. 40).
· The Court in Bradshaw sets out a restrictive approach as to when a trial judge can rely upon corroborative evidence in the assessment of substantive reliability. At para. 57 Karakatsanis, J. states:
…to determine whether corroborative evidence is of assistance in the substantive reliability inquiry, a trial judge should
1. Identify the material aspects of the hearsay statement that are tendered for their truth;
2. Identify the specific hearsay dangers raised by those aspects of the statement in the particular circumstances of the case;
3. Based on the circumstances and these dangers, consider alternative, even speculative, explanations for the statement; and
4. Determine whether, given the circumstances of the case, the corroborative evidence led at the voir dire rules out these alternative explanations such that the only remaining likely explanation for the statement is the declarant's truthfulness about, or the accuracy of, the material aspects of the statement.