How can I defend the charges if the machine says I blew over 80?

By Last Updated: June 14, 2022

How can I defend the charges if the machine says I blew over 80If you provided sample of your breath and the machine said you blew over the legal limit, you have likely been charged with driving with a blood alcohol over the legal limit (s. 253(1)(b) of the Criminal Code).  This is known as an “Over 80” or “Over .08” charge.  The reason the 80/.08 is relevant is because the criminal legal limit in Canada is 80/.08.   The 80/.08 actually refers to a concentration of alcohol in the blood.  For example, if someone blows, 80/.08, it means that the person’s blood alcohol level is 80 milligrams or .08 grams of alcohol in 100ml of blood.  So every 100ml of blood in that person’s body contains 80mg/.08g of alcohol.  This is known as someone’s BAC (Blood Alcohol Concentration).  The Criminal Code expresses the offence in milligrams, so although many people use the .08 terminology, the more appropriate expression of a BAC is in milligrams, which is what we’ll use.

Also notice that the charge is not just 80, but rather over 80.  Sometimes, even the police get this wrong, but it’s actually not an offence under s. 253(1)(b) of the Criminal Code to drive with a BAC of 80.  It’s only an offence if the BAC is over 80.

Over 80 litigation is an extremely technical area of law. Just because the machine said your BAC is over the legal limit does not mean you were in fact over the legal limit, nor that you will be found guilty.  Whole books have been written just on the topic of “Over 80” defences, and it is the job of a competent DUI lawyer to be well versed in each and every defence.  While all the available defences are just too numerous to list, there are two major categories.  There are the “Charter” defences, and the “non-Charter” defence.

The category of “Charter” defences refers to the requirement that in conducting their investigation the police respect all your constitutionally protected rights under the Charter of Rights and Freedoms. Consider that the central evidence against you in an “Over 80” prosecution is the Certificate of a Qualified Technician.  This document states what you blew, and is produced only at the very conclusion of the entire investigation.  Think of the whole investigation leading up to the production of that document as a chain being pulled out of the water with the Certificate being tied to the bottom end of the chain.  If anywhere along that chain, the police violate your Charter rights, it’s the equivalent of breaking a link in the chain.  Breaking any link in the chain collapses the whole thing, and the certificate strapped to the end falls back into the water, never to be seen by the judge.

So how strong are the links, you might ask? Although the onus is typically on you ( and your lawyer) to show that the police violated your Charter rights, some violations are presumed to have occurred in virtually every “Over 80” case. Particularly with cases where someone is alleged to blow over the legal limit, the police conduct a warrantless search each time they take a sample of breath from the detainee. As such, the prosecutor must prove that each step in the breath testing process and sequence is authorized by law. This search must be conducted in a manner that is consistent with law, and if it is not, requiring you to provide a sample of your breath violates your constitutionally protected right to be free from unlawful search and seizure. If your constitutionally protected rights are violated during the arrest, the Judge must determine whether admitting the results of your breath test will bring the administration of justice into disrepute. If the Judge determines that the administration of justice will be harmed by the admission of your breath sample results, these results will be excluded from the trial and you will be acquitted of blowing over the legal limit.

Beyond the “Charter” defences, there are still a myriad of defences dealing with the reliability of the breath tests.  Just because the machine spit out a reading that is over the legal limit doesn’t necessarily mean it’s accurate.  Even if it is accurate, it doesn’t mean your BAC was over the legal limit at the time of driving.

An experienced criminal lawyer will review the breath testing documents to see if the instrument taking the breath samples (currently the EC/IR II) was properly calibrated and maintained. Likewise, it is important to review the breath testing procedure to ensure the instrument was operated properly by the breath technician.  The breath testing instruments are not infallible. Mouth alcohol, improper calibration, and operator error can all lead to erroneous results, and it’s our job as criminal defence lawyers to spot these issues if they occurred.  As you can probably tell if you’ve read to the end of this write-up, this area of law is incredibly dense and complicated. Consulting a criminal defence lawyer with experience in impaired driving defence will greatly improve your ability to fight the charges you face.

About The Author

Michael Oykhman

Managing Partner

Michael Oykhman is a senior lawyer and founder of Strategic Criminal Defence, a full-service criminal law firm with central law offices across Western Canada and Ontario.

My professional experience consists of countless court appearances and thousands of successful defences and satisfied clients. Over the last 10 years, I have worked to build a law office where all the lawyers share our collective experience, resources, and passion to help people. Our team approach to legal representation is client–rather than only law–centred. We look for opportunities to add value to our clients through strategic thinking and creative solutions.

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