Is Blood Alcohol Evidence Frequently Disputed in Ontario DUI Trials?

You have just left a bar near your house. It was a good time, you were with some old friends you had not seen in a while, and a little after 1 a.m., you called it a night. You live close by and you still felt pretty sharp, so you decided to drive home to avoid having to come back to get your car in the morning. Unfortunately, you got pulled over and you blew over the legal limit. Now you are  facing impaired driving charges. 

It’s a story experienced DUI lawyers have heard many times. As trial approaches, people facing DUI charges often ask, “Is blood alcohol evidence frequently disputed in Ontario DUI trials?” The short answer is yes. But in this blog we’ll cover exactly how blood alcohol evidence works and introduce some common defences and constitutional arguments criminal defence and DUI lawyers use.

 

Blood Alcohol Concentration (BAC) and Test Methods

Blood alcohol concentration (BAC), synonymous with blood alcohol content, measures the amount of alcohol in your bloodstream. In Ontario, the legal limit for drivers is set at a BAC of 0.08%. A BAC of 0.08% means that there are 0.08 grams of alcohol per 100 millilitres of blood in the body. At this level, an operator of a conveyance (i.e., motor vehicle, vessel,  aircraft, or railway equipment) is considered to be over the legal limit of BAC in Canada and can be charged under section 320.14(1) of the Criminal Code with having a BAC that is equal to or greater than 80 mg of alcohol in 100 mL. of blood. Many studies have shown that a person’s ability to drive safely at BAC concentrations of .05% or over may be compromised due to the effects of alcohol on their cognitive and motor functions. The studies have further found that at BAC levels of 0.10% or over, everyone’s ability to operate a motor vehicle is impaired by alcohol.  

Authorities determine BAC through two primary methods: Intoxilzyer tests (the older instruments were called breathalyzers and many people still use this term) and blood samples. These tests provide a clear, quantifiable basis upon which it can be determined whether or not a driver has committed an impaired driving or DUI offence. 

 

The Role of BAC in Impaired Driving Charges

The Criminal Code and the Highway Traffic Act govern impaired driving law in Ontario. As mentioned above, these laws stipulate that a high blood alcohol concentration (0.08% or higher) constitutes legal impairment, and the offending driver may be charged. That said, you can also face penalties like a temporary suspension for registering a warning level BAC on an alcotest roadside screening test. A warning level BAC on a roadside screening breath test is between 0.05% and 0.10%. Alcotest screening devices are calibrated to fail at 0.10%. If a driver fails an alcotests (i.e., registers a BAC of 0.10% or over), they will be arrested and taken to the police station for the “real” Intoxilyzer breath tests to determine if they are over or under the legal BAC limit. In certain situations, the police can also demand that a person provide a sample of their blood, or they may seize a person’s blood at the hospital pursuant to a valid search warrant. 

When it comes to novice drivers and those under 22 years old, Ontario enforces a zero-tolerance policy, where any detectable BAC level leads to charges under the Highway Traffic Act.  Commercial drivers are also held to stricter standards, given their increased level of responsibility.

The penalties for exceeding legal BAC limits in Ontario are severe: they range from mandatory minimum fines and driving suspensions and sometimes even jail for first-time offenders, to extended jail time for repeat offenders, or where bodily harm or death occurs. However, working with an experienced DUI lawyer can help you mitigate some or all of these consequences and in many cases, avoid a criminal record. 

 

DUI Trial Blood Alcohol Disputes

Disputing a DUI charge based on Blood Alcohol Concentration (BAC) during a trial often hinges on challenging the accuracy and reliability of the BAC test results.

Defence strategies for DUI cases might include questioning the calibration, maintenance records,  or operation of intoxilyzer devices, as these instruments need regular and precise calibration to provide an accurate reading of a person’s blood alcohol level. The defence may also scrutinize the procedure followed by the police officer during the entire arrest process and administration of the tests, looking for any deviations from legal protocols and police errors that could affect the outcome. Finally, the defence may be able to exclude the results of the tests based on violations of sections 7, 8 (search and seizure), 9 or 10(b)  (right to counsel) of the Canadian Charter of Rights and Freedoms. For example, violations of an accused’s right to counsel under s. 10(b) of the Charter, resulting in exclusion of the breath or blood samples under s.24 of the Charter, is one of many common ways to win a DUI trial. 

Another approach could be to examine the blood sample handling and storage processes. Mishandling or contamination can lead to the samples being excluded from evidence. Expert witnesses, such as forensic toxicologists, may also be called upon to testify about potential flaws in the testing process or interpret the BAC results in a context that favours the defendant.

As you can see, although BAC readings provide a fixed numerical basis for a DUI case, there are many blood alcohol evidence challenges that a skilled DUI lawyer can use to create reasonable doubt about the reliability of the evidence against you.

 

Kruse Law – Face Your Impaired Driving Charges Head On

Being charged with impaired driving is a difficult situation, but it is not without hope. Having an experienced DUI lawyer in your corner can be the difference between facing heavy legal consequences and having your charges reduced or dismissed.

If you find yourself in such a predicament, seek out the support of a DUI lawyer in Toronto. At Kruse Law, our lawyers will do everything they can to bring about the most favourable outcome for your DUI case. Don’t face the legal system alone; protect your rights and interests with Kruse Law.