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DUI - How to Challenge Breathalyzer Evidence in Ontario

DUI – How to Challenge Breathalyzer Evidence in Ontario

Wondering how to successfully fight a DUI charge in Ontario? You’re not alone. One of the key elements in many DUI cases is the breathalyzer test, also known as the “Over 80” test in Ontario. In this simplified guide, we’ll walk you through how to challenge DUI breathalyzer results and the reasons why your DUI case could be dropped.

What is the Over 80 DUI Charge in Ontario?

If you’re facing an “Over 80” DUI charge in Ontario, it means you’ve been tested and found to have more than 80 milligrams of alcohol per 100 millilitres of blood. The prosecutors, commonly known as crown lawyers, will try to use these breathalyzer readings to prove you’re guilty of DUI.

How to Challenge the Integrity of DUI Breathalyzer Results

Challenging the validity of your breathalyzer test is a common defence strategy used by DUI lawyers. Here’s how it can be done:

1. Was the Observation Period Properly Followed?

Before you blow into the breathalyzer, the technician needs to observe you for a certain period. They’re making sure you aren’t eating, drinking, or belching—any of which could skew the results. If they fail to properly monitor you, the breathalyzer test results could be thrown out, weakening the crown’s case against you.

2. Was There a Technician Error?

People aren’t perfect, and that includes breathalyzer technicians. If the technician made errors while setting up, calibrating, or taking breath samples, those mistakes could invalidate your test results. If this happens, there’s a good chance your DUI case could be dismissed.

3. Were Your Rights Violated?

In Ontario, you have the right to consult with a lawyer upon arrest, thanks to the Charter of Rights and Freedoms. If, for instance, the police eavesdrop on your lawyer consultation, your rights are violated. This breach could lead to your case being withdrawn, even if your DUI breathalyzer results were otherwise valid.

4. Were There Legitimate Grounds for Your Arrest?

According to the Charter, police must have a valid reason to believe you were driving under the influence. Simply smelling alcohol or seeing red eyes isn’t enough. If the police can’t prove they had a good reason to arrest you, your breathalyzer results may not be considered valid evidence.

Summary: How to Win Your DUI Case by Challenging the Breathalyzer

Challenging the DUI breathalyzer test in Ontario can be an effective way to fight an “Over 80” charge. Whether the issue lies with the observation period, technician errors, violations of your rights, or the legitimacy of your arrest, any one of these factors could weaken the crown’s case against you. Remember, consult a legal expert for personalized advice on how to best handle your DUI case.

How can I challenge the breathalyzer evidence in my DUI case in Ontario?

One potential argument is that the observation period before administering the breath test was not properly followed. This could undermine the credibility of the breath results and potentially exclude them from being used as evidence in your case. Another argument is that there were mistakes made by the breath technician during the setup, calibration, or collection of the breath samples. If mistakes were made, it could compromise the credibility of the breath readings. Lastly, the police may not have had reasonable and probable grounds to arrest you for DUI, which could also potentially exclude the breath test results as evidence.

What are some common ways to challenge breathalyzer evidence in a DUI case in Ontario?

Potential challenges include the following. Observation period not correctly followed could potentially undermine the credibility of the breath test results and exclude them from being used as evidence. Technician errors during the setup, calibration, or collection of breath samples could also compromise the credibility of the breath readings. A violation of your right to speak with a lawyer during your arrest could also potentially exclude the breath test results as evidence.

The Ontario DUI Arrest Test

The 60-Second Ontario DUI Arrest Test assesses the nature of the arrest in order to determine if your charges may get withdrawn.

Do You Want to Keep Driving?
Dan Joffe, lawyer, partner Nextlaw Ontario

My team uses forensic analysis to determine whether your Charter rights were violated. If you have been charged with DUI, book a free call that can change everything

Do you want to avoid a DUI Charge?

My team uses forensic analysis to determine whether your Charter rights were violated. If you have been charged with DUI, book a free call that can change everything

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About Dan Joffe, Partner

Daniel holds a JD (LLB) / MBA from Osgoode Hall Law School & the Schulich School of Business at York University, Toronto. Dan is a licensed lawyer in the Province of Ontario.

The Ontario DUI Arrest Test™

The 60-Second Ontario DUI Arrest Test assesses the nature of the arrest in order to determine if your charges may get withdrawn.

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Next Law publishes these articles and videos as a service to our website visitors for general informational purposes only. These materials do not, and are not, intended to, constitute legal advice. You should not act upon any such information without seeking professional counsel.