Most police officers in BC carry handheld breathalyzer devices – Approved Screening Devices (“ASD”) – in their vehicles. Officers use ASD’s at the roadside to screen for impaired drivers. If you are driving a vehicle in British Columbia and you are stopped by a police officer, you may be required to provide a breath sample – even if you do not display any signs of impairment. Due to recent changes in federal law, police in Canada do not require any evidence that you have been drinking in order to make you blow. 

If a driver blows and fails an ASD test, they will face severe penalties. The driver may be charged criminally, or they will be given an Immediate Roadside Prohibition (IRP). An IRP means a suspension from driving for 90 days, and a vehicle impound for 30 days.  The driver will also face hefty fines and must participate in expensive and time-consuming remedial programs. In most cases in BC, drivers who fail a roadside breath test will be given an IRP.

Under the Motor Vehicle Act, if a driver subjected to an IRP investigation blows a fail on an ASD, police are required to offer the driver an opportunity to provide a second sample on a different ASD. This is important – under the law, police must inform the driver of their right to a second test on a different machine, but the driver is not required to take the second test.

Police often attempt to pressure drivers into taking the second test because it tends to “lock in” and confirm the results of the failed first test. Officers may try to convince drivers that they have “nothing to lose” and it can only “help their situation”. They may claim that the second test could result in a lower reading. While this is theoretically possible, it is extremely unlikely as the second test is almost always administered by police immediately after the first and the factors that caused the fail in the first place would still be present – particularly after a false fail.

For example, mouthwash, chewing tobacco, and certain chocolates and candy contain alcohol in various amounts. This can cause a false fail on an ASD. This problem arises because ASD’s are not capable of telling the difference between mouth alcohol present from one of these substances, and deep lung alcohol present as a result of alcohol consumption. In other words, a driver can fail an ASD test if they did not drink any alcohol but recently rinsed with mouthwash; hard to believe but true. In such a situation the police would almost always offer another test immediately after the first test. The second test would most certainly result in another fail reading which would make the IRP much more difficult to appeal.

There are many defences to an IRP. Most are technical in nature – but a good one is when an issuing officer does not advise the driver of his or her right to a second test on a different machine – in that case the IRP cannot stand, and an IRP adjudicator must revoke it.  A driver should be careful though as some IRP Adjudicators have upheld IRP’s where a driver elected not to take the second test. This is wrong in law as the second test is optional. However, if the officer did not offer the second test and the driver only provided one sample, that is a clear defence to the IRP.

Police are required to test and calibrate the ASD’s that they use in the course of these duties. They must be tested by a certified calibrator once a month. A positive calibration only means that the unit is working at that time it was tested. A positive calibration does not guarantee the machine will function properly when it leaves the lab. These machines get bounced around in the back of police vehicles and are subject to fluctuations in weather and temperature.  They can, and do, frequently malfunction and it is usually easier to challenge the results of one bad test on a malfunctioning machine, than two.  

*Note that an IRP investigation is distinct from a criminal impaired driving investigation. Under a criminal impaired investigation, a driver is required to provide a breath sample and if the driver fails that test, he or she will be arrested and taken to the police station.  The driver should speak with a lawyer immediately. The driver will then be required by police to provide a second breath sample – in this case, the driver does not have the choice to decline the second test.

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