The appellant was charged with operating a motor vehicle with a blood alcohol concentration exceeding 80 mg percent, contrary to s. 320.14(1)(b) of the Criminal Code.
The Crown sought to rely on the statutory presumption of accuracy under s. 320.31(1)(a), adducing the certificate of the qualified technician and two analyst certificates.
The central issue was whether the Crown must prove, not merely disclose, the target value of the alcohol standard used in the system calibration check in order to rely on the presumption of accuracy.
The majority held that while the target value must be disclosed pursuant to s. 320.34(1)(b), it need not be independently proven at trial as a precondition to the presumption of accuracy, as Parliament did not intend it to be a statutory precondition.
Côté J. dissented, finding that both disclosure and proof of the target value are constitutionally required to preserve the presumption of innocence and the accused's right to make full answer and defence.
