DUI in Ontario – Breathalyzer False Positive Readings

• Can a breathalyzer test result in a false-positive reading, leading to an unjust DUI charge in Ontario?
• And the answer is, yes.
• That’s what I am going to cover in this article.
• In Ontario, a breathalyzer device is used by the Police to measure blood alcohol content, known as BAC.
• If your BAC is above 0.08, then you will be charged with a DUI.
• Specifically, you’ll be charged with an Over 80, and likely, a second charge of operating a vehicle while impaired by alcohol or drug.
• But these breathalyzer devices are not perfect.
• And there are some cases where you may get a false positive on your breathalyzer result which means your DUI charge would get withdrawn.
• Let me take you through a few examples.

1/ Health Conditions

• Certain health conditions can cause a positive BAC reading even without consuming alcohol. 
• Acetone, which is a naturally occurring compound in the body, can cause false positives. 
• For instance, a diabetic with hypoglycemia may have a BAC of 0.06, which combined with even one drink, can put them over the limit. 
• Gastrointestinal issues like acid reflux and heartburn can also cause false positives on breathalyzer tests.

2/ Diet

• Your eating habits can affect the outcome of a breathalyzer test. 
• Popular low-carb diets like Atkins and Keto can increase acetone levels, leading to false positives. 
• Foods like protein bars, nuts, bread, energy drinks, ripe fruits, and sugarless gum, which use fermentation as a preservative, can also cause false positive readings.

3/ Improper Device Calibration

• If a breathalyzer device is not properly maintained and calibrated, it can result in false readings.
• These breathalyzer devices must be properly calibrated and adjusted for the temperature to ensure accurate readings.

4/ Improper Test Administration

• To get an accurate BAC reading, a breathalyzer test must be administered correctly. 
• Prior to the start of your breath test, you need to be observed for 15 to 20 minutes.
• And any instances of burping, vomiting, or acid reflux resets the clock, and the breath technician will need to wait another 15 minutes before administering a new test.
• There are other examples of situations which may produce a false positive result.
• The big takeaway is this.
• A good DUI lawyer will get all the evidence and dig deep to see if there are any issues that would undermine the credibility of the breathalyzer test results.