Breathalyzer Calibrations & DUI Defence
Breathalyzer evidence is often central in DUI cases. However, the law requires that these machines be properly tested, maintained, and calibrated before they are used. If the device is not shown to be working properly, the results may not be reliable.
In this case, a careful review of the evidence revealed serious issues with the calibration of the breathalyzer. As a result, the court found that the demand was not lawful and the charge was dismissed.
If you need to speak to a criminal lawyer, call Charitsis Law today at 647-930-0200.
What Is Breathalyzer Calibration?
Breathalyzer machines, including Approved Screening Devices (ASDs), must be regularly tested and calibrated to ensure accuracy. In most cases:
- devices are calibrated every 14 days
- calibration records are maintained by police
- officers are trained not to use devices without proof of calibration
If there is no reliable evidence that the device was properly calibrated, the court may question whether it was capable of producing an accurate result.
Facts of the Case
Mr. Washington was stopped by police during a roadside investigation and was required to provide a sample of his breath using an Approved Screening Device (ASD). The officer made a formal demand under the Criminal Code and expected a sample to be provided immediately.
According to the police, Mr. Washington failed to comply with that demand. As a result, he was charged with refusing to provide a breath sample, which carries serious criminal consequences similar to a DUI charge or impaired driving.
However, what actually happened at the roadside was not a clear refusal.
Mr. Washington made several attempts to provide a breath sample. Despite these efforts, the device did not produce any result. There was no “Pass,” “Warn,” or “Fail” reading recorded by the machine.
At the time, the situation was treated as a refusal. However, no one could confirm whether the problem was with Mr. Washington’s efforts or with the breathalyzer device itself.
It was only later, during the court process, that a critical issue came to light. The breathalyzer used that night had not been properly calibrated within the required timeframe. This raised serious concerns about whether the machine was capable of analyzing a breath sample at all.
The case ultimately turned on this question: did Mr. Washington refuse to provide a sample, or was he unable to comply because the device was not working properly?
That issue became the focus of the trial.
Issues at Trial
The case focused on whether the Crown could prove that Mr. Washington refused to comply with a lawful demand.
Key issues included:
- Calibration Evidence The Crown did not establish that the device had been calibrated within the required 14-day period. This raised concerns about reliability.
- Working Condition Without proof of calibration, there was no clear evidence that the machine was capable of producing a proper analysis.
- Lawful Demand A refusal charge requires a valid demand. If the device was not working properly, the demand may not have been lawful.
- Attempts to Comply Mr. Washington made several efforts to provide a sample, which challenged the allegation that he refused.
These issues were critical because a refusal charge cannot succeed unless the demand itself is lawful.
The Law on Breath Demands
Under the Criminal Code, a driver is required to provide a breath sample when a police officer makes a lawful demand. However, the law does not allow police to rely on assumptions—the demand must be grounded in proper procedure and reliable equipment.
For a breath demand to be lawful, several legal requirements must be met:
- Properly Functioning Device The officer must be using an Approved Screening Device that is capable of providing a reliable analysis. If the machine is not proven to be working properly, the entire demand may be invalid.
- Reasonable Belief The officer must honestly believe the device will produce a proper result, and that belief must also be objectively reasonable based on the circumstances.
- Calibration and Maintenance There must be evidence that the device was properly tested and calibrated within the required timeframe. Without this, the reliability of the machine is called into question.
- Ability to Analyze Sample The device must be capable of analyzing the breath sample at the time of the demand. If the machine cannot produce a result, it undermines the legality of the process.
When these requirements are not met, the law is clear—the accused is not obligated to provide a breath sample. This is a critical point that can directly impact whether a refusal charge can be proven in court.
Why the Case Fell Apart
The defence focused on the reliability of the breathalyzer and whether the Crown could prove that it was functioning properly at the time of the demand. Without this proof, the entire foundation of the charge became questionable.
The court heard several key issues that weakened the Crown’s case:
- Missing Calibration Evidence The Crown did not provide proof that the device had been calibrated within the required 14-day period. This raised serious concerns about whether the machine could be trusted.
- No Recorded Result The device failed to produce any “Pass,” “Warn,” or “Fail” reading. This suggested that the machine may not have been capable of analyzing a sample at all.
- Uncertain Reliability Without proper calibration records, there was no clear evidence that the device was in proper working order. This created doubt about whether the test could have been completed even if the accused tried.
- Efforts to Comply The evidence showed that Mr. Washington made multiple attempts to provide a breath sample. This directly challenged the allegation that he refused.
When these issues were considered together, the Crown could not prove that the breath demand was lawful. This created a significant gap in the case and ultimately led to its failure.
Judge’s Decision
The court found that the Crown Attorney failed to prove beyond a reasonable doubt that the breath demand was lawful. Without reliable evidence that the device was properly calibrated and functioning, the demand could not be enforced.
The judge accepted that there was a real possibility that the machine was not capable of producing a proper analysis. In that situation, the accused could not be found guilty of refusing to comply.
Because the demand was not proven to be lawful, the refusal charge could not succeed. The court dismissed the charge, and the accused was found not guilty.
What This Means for Your Case
Breathalyzer evidence is often treated as strong evidence in DUI cases, but it is not immune from challenge. The Crown must prove that every step of the process was carried out properly, including the condition of the device itself.
A strong defence strategy focuses on identifying weaknesses such as:
- Calibration Gaps Reviewing whether the device was properly tested and maintained can reveal critical flaws in the Crown’s case.
- Procedural Errors Any failure to follow proper legal steps can affect whether the demand was valid in the first place.
- Unreliable Results If the device does not produce a clear result, this raises serious doubt about its reliability.
- Actual Conduct of the Accused Evidence that the accused attempted to comply can undermine the allegation of refusal.
These factors can create reasonable doubt and significantly improve the chances of having charges withdrawn or dismissed. A detailed review of the evidence is often the key to identifying these issues.
Speak With a Criminal Defence Lawyer
If you are facing a DUI or refusal charge, it is important to understand that the case may not be as straightforward as it appears. The reliability of the evidence and the legality of the police procedure must be carefully examined.
A criminal defence lawyer can review your case, explain your options, and identify legal issues that could lead to a successful outcome. Many people are not aware of the possible defences available to them until the evidence is fully analyzed.
Call Charitsis Law at 647-930-0200 for a free and confidential discussion. Speak directly with a criminal lawyer and get clear guidance on your case and your next steps.
