A statutory presumption violates the right to be presumed innocent if its effect is that an accused person can be convicted even though the trier of fact has a reasonable doubt

R. v. St‑Onge Lamoureux, 2012 SCC 57 sets out the test for determining when a statutory presumption violates the presumption of innocence:

[24]                          A statutory presumption violates the right to be presumed innocent if its effect is that an accused person can be convicted even though the trier of fact has a reasonable doubt (R. v. Vaillancourt, [1987] 2 S.C.R. 636, at pp. 654‑56; Downey, at p. 21).  In R. v. Whyte, [1988] 2 S.C.R. 3, the Court stressed that the distinction between elements of the offence and other aspects of the charge is irrelevant to the analysis regarding the right to be presumed innocent.  "If an accused is required to prove some fact on the balance of probabilities to avoid conviction, the provision violates the presumption of innocence because it permits a conviction in spite of a reasonable doubt in the mind of the trier of fact as to the guilt of the accused" (p. 18).  What is important for the purpose of determining whether the right to be presumed innocent is violated is not whether the statutory presumption relates to an essential element of the offence, but whether it exempts the prosecution from establishing the guilt of the accused beyond a reasonable doubt before the accused must respond (Oakes, at p. 121; R. v. Dubois, [1985] 2 S.C.R. 350, at p. 357).  Thus, like the presumption at issue in Oakes, the ones established in s. 258(1)(c) will violate the right to be presumed innocent if they can result in the conviction of an accused in spite of a reasonable doubt that the accused is in fact guilty.