Exposé juridique sur ce qu'était la preuve contraire avant C-2 (2 juillet 2008)

R. c. Dubois, 1990 CanLII 2776 (QC C.A.)

Section 253(b) of the Criminal Code creates the offence of operating (or having care or control) of a motor vehicle while one's blood-alcohol level exceeds eighty milligrams of alcohol in one hundred millilitres of blood. That offence may be proved in various ways. Normally, it is established by evidence of breathalyzer results. If the tests are conducted as required by the Code, they may be relied upon as proof of guilt -- but only where there is no contrary evidence as to the blood-alcohol level of the accused at the time the offence is alleged to have been committed: R. v. Moreau, 1978 CanLII 162 (S.C.C.), (1979) 1 S.C.R. 261; Piuze v. A. G. Ouébec, C.A.Q. 200-10-000043-872, March 28, 1988; R. v. Carter 1985 CanLII 168 (ON C.A.), (1985), 19 C.C.C. (3d) 174 (Ont. C.A.) R. v. Davis (1973), 14 C.C.C. (2d) 513 (B.C.C.A.).

Thus, s. 258(1) (c) of the Code does not impose an "ultimate" or "persuasive" burden of proof on the accused. The "evidence to the contrary" to which it refers must tend to show -- but it need not prove -- that the blood-alcohol level of the accused did not exceed the statutory limit at the relevant time. The exculpatory evidence, in other words, must have probative value, but it need not be so cogent as to persuade the court.

If the trier of fact considers that the "evidence to the contrary" raises a reasonable doubt or, as is sometimes said, that it might reasonably be true, then the incriminating breathalyzer result will no longer support a conviction: see R. v. Proudlock (1978), 43 C.C.C. (2d) 321 (S.C.C.) at pp. 325-26, where Pigeon J., for the majorityt equates the effect of a presumption of fact of the kind that arises from possession of recently stolen goods with the effect of a statutory presumption of the kind created by s. 258(1)(c) of the Code.

See, as well, Cross on Evidence, 6th ed., particularly at pp. 135 and 140, concerning the discharge of an evidential burden by evidence which suggests a "reasonable possibility" of innocence.

Delivering the unanimous reasons of the Privy Council in Javasena v. The Queen, (1970) A.C. 618 at p. 624, Lord Devlin discusses the evidential burden in terms of "enough evidence to suggest a reasonable possibility" (my emphasis). In the same case, his Lordship reiterates that it is "sufficient (for the accused) to raise a doubt as to his guilt" or "to collect from the evidence enough material to make it possible for a reasonable jury to acquit" (at p. 623). Finally, see R. v. Oakes 1986 CanLII 46 (S.C.C.), (1986) 24 C.C.C. (3d) 321 (S.C.C.), particularly at p. 330, where Chief Justice Dickson discusses the nature and rebuttal of presumptions.

In my respectful view, then, a breathalyzer result cannot support a conviction under s. 253 if there is contrary evidence which raises a reasonable doubt or suggests a reasonable possibility of innocence or might reasonably be true.

"Evidence to the contrary" that is disbelieved will, of course, fail to neutralize, or to render inoperative, the presumption created by s. 258(1) (c) of the Code.