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DUI Defense 2 Hour Rule (1)

Ontario DUI Defense: 2-Hour Rule You Need to Know

Are you facing DUI charges in Ontario? Your defence could hinge on a crucial timeline that many people don’t even know exists – the two-hour rule. As a DUI defence lawyer at NextLaw, I’ve seen how understanding this rule can completely change the outcome of a DUI case.

Understanding the Two-Hour Rule and Its Impact

In this comprehensive guide, you’ll discover three critical aspects of the two-hour rule that could significantly affect your DUI case:

What Is the Two-Hour Rule?

Timing becomes crucial when you’re pulled over and arrested for a DUI. The two-hour rule states that police must conduct your first breath test within two hours of your last driving moment – not from when they pulled you over or arrested you.

This isn’t just a procedural guideline. It’s a fundamental part of our criminal law that states it’s an offence to have a blood alcohol concentration at or over 80 milligrams per 100 millilitres of blood within two hours of driving. Importantly, breath test results are only accepted as evidence of your blood alcohol level while driving if the test occurs within this two-hour window.

The Critical Testing Timeline

Let’s break down a typical scenario:

  • You’re pulled over at 11:30 PM
  • The officer conducts their investigation
  • They call for a breath technician
  • You’re transported to the station
  • The first breath test is administered

Here’s the crucial part: everything changes if that first breath test happens at 1:31 AM – just one minute after the two-hour mark.

Why Timing Changes Everything

The Crown needs two separate breath samples as evidence, using the lower of these readings. However, if the first test occurs even slightly after the two-hour window, they need additional support: a toxicologist’s testimony. This expert must calculate backward and testify about your probable blood alcohol level at the time you were driving.

DUI HOW TO DEFEND

Using the Timeline as Your Defense Strategy

When reviewing a DUI case, the timing of events becomes a critical factor in building a defence. If the police conducted the first test outside the two-hour window, it would create powerful grounds to challenge the evidence.

Key Defense Implications:

  • Without a toxicologist’s testimony, the Crown may struggle to prove their case
  • The Crown must prove your blood alcohol concentration was over the legal limit while driving, not just at testing
  • Getting expert testimony is expensive and complex, often costing thousands of dollars
  • This additional layer of complexity can significantly impact the Crown’s case

The Impact on Your Case

The two-hour rule isn’t just a technicality – it could be the difference between a conviction and an acquittal in your Ontario DUI case. Understanding this timeline is crucial for the following:

What is Ontario's two-hour rule in DUI cases?

Ontario's two-hour rule requires police to conduct your first breath test within two hours of your last driving moment. This timeline is critical for determining the admissibility of your blood alcohol level as evidence in court.

How can the two-hour rule help my DUI defence?

If the first breath test occurs outside the two-hour window, the prosecution may need a toxicologist's testimony to prove your blood alcohol level while driving, making their case more challenging and complex.

The Ontario DUI Arrest Test

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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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Disclaimer

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.