Mr. Rousselle was arrested for impaired driving and administered a breathalyser test. Based on the results of the test, he was charged with having a blood alcohol concentration equal to or exceeding 80 mg of alcohol in 100 mL of blood within two hours of ceasing to operate a motor vehicle. At trial, a Certificate of Qualified Technician from the officer who administered the breathalyzer test was admitted into evidence but the trial judge refused to admit two certificates of analysts who had certified the target value of the alcohol standard used by the qualified technician to conduct a required system calibration check of the breathalyzer device. The trial judge held the Certificate of Qualified Technician was not evidence of the target value of an alcohol standard and proof of the target value of an alcohol standard was a pre-condition to the Crown relying on the presumption in s. 320.31(1) of the Criminal Code that breathalyzer test results are conclusive proof of blood alcohol concentration. The trial judge acquitted Mr. Rousselle. A summary conviction appeal was allowed, the acquittal was set aside and a conviction was entered. The Court of appeal dismissed an appeal. Argued Date 2025-04-24 Keywords Criminal law — Evidence — Breathalyser test results — Target value of alcohol standard — Whether Court of Appeal erred in interpretation of s. 320.31(1)(a) of Criminal Code as permitting Crown to prove alcohol standard was certified by an analyst through hearsay evidence of qualified technician? Notes (New Brunswick) (Criminal) (By Leave) Language English Audio Disclaimers This podcast is created as a public service to promote public access and awareness of the workings of Canada's highest court. It is not affiliated with or endorsed by the Court. The original version of this hearing may be found on the Supreme Court of Canada's website. The above case summary was prepared by the Office of the Registrar of the Supreme Court of Canada (Law Branch).