R. v. Goleski, 2014 BCCA 80:
Elements of Failure/Refusal
 As discussed in Lewko at para. 9, the elements of the offence that the Crown must prove are: (i) a proper demand; (ii) a failure or refusal to provide the required breath sample; and (iii) an intention to fail or refuse to provide the required sample. In R. v. Moser 1992 CanLII 2839 (ON CA), (1992), 71 C.C.C. (3d) 165 at 176 (Ont. C.A.), Mr. Justice Doherty said this:
The essential elements of the offence described in s. 254(5) consist of a proper demand and a refusal or failure to comply with that demand. The defence of “reasonable excuse” is not a denial of either of those essential elements but refers to “matters which stand outside the requirements which must be met . . . before a charge can be supported”: per Laskin J. in Taraschuk v. The Queen (1975), 25 C.C.C. (2d) 108 at p. 110, 62 D.L.R. (3d) 84,  1 S.C.R. 385. The defence of “reasonable excuse” is engaged only after the Crown has proved a proper demand and a failure or refusal to comply with that demand.
 Also germane is the following from the reasons of Judge Gorman in R. v. Sheehan (2003), 35 M.V.R. (4th) 61 (N.L. Prov. Ct.):
 In my view, the actus reus of this offence is the failure or refusal to comply with the demand. The mens rea element requires that the failure or refusal to comply be intentional. Therefore, a person who fails to provide an appropriate sample despite genuinely attempting to do so, will not have committed the mens rea of this offence. It is important to keep in mind that this has nothing to do with whether or not the accused had a reasonable excuse.