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Innocent of impaired driving in BC

Innocent of impaired driving in BC

Mouth alcohol from regurgitated stomach contents are a threat to reliable breathalyzer samples

As the annual BC Christmas Counter Attack campaign gets underway, and with the news that Manitoba is introducing an Immediate Roadside Prohibition (IRP) scheme modelled on ours here in BC, we thought it was an appropriate time to discuss those who are innocent of impaired driving in BC. An argument we often hear is that people accused of impaired driving and who succeed in challenging the breath-test readings merely got through due to a technicality. The assumption is that an over .08 reading is enough to assume guilt. The problem with that type of thinking is that it ignores the many reasons why breath-test readings may be inaccurate. In certain circumstances, you simply can’t rely on the breath readings which is why some people are actually innocent of impaired driving.

Mouth alcohol – the biggest threat to reliable testing

From the early days of alcohol breath testing, scientists identified residual mouth alcohol as the biggest threat to obtaining reliable breath-alcohol tests. There are two ways that a person can have residual alcohol in their mouth; either from a recently consumed drink or from regurgitated stomach contents.

Of the two quality assurance steps, only one is employed at the roadside.

In BC the police are instructed to ask questions to determine the time of the last drink. The purpose of this is to determine whether a recently consumed drink will cause a falsely high reading. Tests that are taken within 15 minutes of the time of the last drink are presumed to be inaccurate because of mouth alcohol. The idea is that if it is more than 15 minutes from the time of the last drink, alcohol from the last drink will probably have dissipated and no longer negatively impact the results.

The timing of the last drink only arises in roadside testing situations. When a driver is stopped by the police, the officer does not know where the person has been, whether they have alcohol in their car or when they last consumed anything with alcohol in it. The question is routine but very important. Because the police haven’t observed the person, they can’t say whether the test may or may not be contaminated from a recent drink without first confirming whether there has been a recent drink.

When the testing is done at a police detachment, the police know there has been no consumption in the 15 minutes up to the test because the subject has been in police custody for longer than that. So at the detachment, the timing of the last drink is not usually an issue.

With tests taken at the detachment, there is almost no chance that a recent drink will contaminate the breath sample. There remains, however, the issue of regurgitated alcohol. This is a major concern. As a consequence, to address this concern, the police are required at the detachment to conduct an uninterrupted face-to-face observation period before obtaining each of the breath samples to ensure that the subject has not burped, belched or otherwise regurgitated stomach contents. If there is an indication that the subject may have regurgitated stomach contents, a sample taken within 15 minutes of the regurgitating event can be expected to be unreliable.

The idea here is to identify who is innocent of impaired driving and who is actually over the limit. A sample in circumstances where mouth alcohol is expected to be present is an unreliable sample.

What about roadside samples?

It’s good that police ask questions about the last drink and it’s good that they conduct an observation period for people who provide samples at a police detachment. But what about regurgitated mouth alcohol at the roadside?

Detachment samples benefit from being taken more than 15 minutes from the last drink AND an observation period to ensure the suspect didn’t regurgitate stomach contents before blowing. These are two essential steps required to obtain reliable tests. At the roadside, blowing into a roadside Approved Screening Device (ASD) the police only fulfill one of these essential steps. Simply put, they have no method to determine whether a breath sample they obtain at the roadside is not contaminated by regurgitated stomach contents.

Of the two quality assurance steps, only one is employed at the roadside. We know that roadside ASD samples, used mostly to issue Immediate Roadside Prohibitions, may be contaminated from either source of residual mouth alcohol. But in BC we only take steps to address one of the two sources. This is a problem.

How big of a problem?   

The government took no steps to determine how big a problem it is that they omit one key aspect of quality assurance in breath testing. It seems that they relied on the police assuring them that this is no big deal. An assurance by the police is really meaningless with nothing to back it up. But that’s what the government did when it created the IRP scheme.

In our view, the government was negligent in this regard. But the question remains, how big a problem is it with the IRP scheme that there is no quality assurance to deal with regurgitated mouth alcohol?

It’s a big problem. Huge actually. How do we know? We took the steps that the government didn’t do to examine how big of a problem regurgitated mouth alcohol is in the IRP scheme.

We have the evidence and we’re going to show it to you. But you’ll need to tune in for our next blog post because we can’t just give it to you without explanatory notes, so stay tuned.

In the meantime, what about people who are innocent of impaired driving in BC but nevertheless receive an Immediate Roadside Prohibition? They have but one avenue to seek a remedy, which is a review before RoadSafetyBC which is where we come in. Give us a call if you have an IRP or impaired driving charge and we will guide you through.

We’re serious about impaired driving defence. Call 604-685-8889

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