DUI, Impaired Driving

What You Need to Know

Impaired driving. Drinking and driving. Driving under the influence, or a DUI. Over 80 blood alcohol content. No matter how it’s described, alcohol-related driving offences are one the most heavily litigated areas of criminal law — but also one of the most defensible. This is due to the often technical and precise nature of the law and instrumentation involved.

In Calgary, approximately 1,500 people are charged with DUIs every year. Drunk driving can occur in all segments of society and is not limited to those individuals who are overtly drunk. Often, those charged with impaired driving offences are ordinary citizens who did not feel drunk at the time, did not act drunk, did not drive erratically, but still provided breath samples in excess of the legal limit.


The expected consequences for being charged or convicted with drinking can be severe.

  • Your driver’s license is suspended from the moment you are charged (not yet convicted) with an impaired driving offence. This suspension lasts until we can get you into trial and deal with the matter. 
  • A DUI conviction results in a 1-year license suspension and driving prohibition. That means no driving anywhere in Canada for a minimum period of one year. 
  • An ignition interlock device may be installed in your vehicle, and a condition placed on your license for a period after your DUI conviction. Your car will only start with the passing of a breathalyzer test (under .05 in Alberta).
  • A DUI is a criminal conviction, which results in a permanent criminal record. 
  • A DUI conviction will automatically register your name to the Canadian Police Information System, which may encourage future attention from authorities.

Beyond this, a criminal conviction can lead to lost employment opportunities, travel restrictions, and the psychological and emotional stigma and consequences of being labelled a ‘criminal’.

How Our DUI Lawyers Can Help

There is a lot we can do if you lost your license by blowing over the legal limit on a breathalyzer or if you have been charged with driving under the influence. Having our DUI attorneys review your case may be the difference between walking away and living with a criminal record.

Strategies For Defence

Dunn & Associates has employed several techniques to fight DUIs in the courtroom:

Questioning the Reliability of the Breathalyzer
Breath instruments, like all machinery or electronic devices, are not infallible. These instruments often fail to record blood alcohol content accurately. If not properly operated, maintained, and updated with the correct software, they can give false readings. We will request the appropriate instrumentation documents and send them to our expert for analysis. Any discrepancies or reliability issues may result in the readings being thrown out of evidence.

Analyzing Varying Blood Alcohol Levels
Unabsorbed alcohol gradually enters your bloodstream. The breath samples used against you in court can only be obtained at checkstop locations, or at the police station itself. Therefore, we sometimes present the case that your blood alcohol level was in fact below the legal limit while driving, prior to providing samples of your breath. Again, a trained expert may be used to extrapolate your blood alcohol reading and provide you with a defence at trial.

Challenging Observations of Impairment
Observations the officer makes with respect to what he/she believes to be ‘physical indicia of impairment’ may have many other feasible explanations. Poor balance may be the result of poor road conditions, slippery footwear, wearing heels, or a knee or hip injury. Slurred speech can be the result of speech impediments, nervousness, or being tongue-tied. Red eyes can result from allergies, cigarette smoke, or fatigue. Unfortunately, it’s been our experience that officers often embellish their notes and investigations in order to make the case seem stronger than what it is. We can expose such exaggerations with a vigorous cross-examination from our lawyers.

Employing Refusal or Failure
In some cases, people are physically unable to provide an adequate sample into the roadside devices or breathalyzer machines. They may suffer from asthma or respiratory issues, or they may have anxiety or be nervous, the police officer may be abusive or threatening, or provide confusing instructions as to how to provide a sample. Sometimes the breath instruments aren’t working and can’t even accept a sample. Based on our complete understanding of the specifics of your case, we can take this approach where appropriate.

Call us. We can help.
If you have been charged with drunk driving, driving while high, an ‘over 80’, or a ‘fail and refuse’, our Calgary criminal lawyers are here to help. Whether it was a momentary lapse of judgment or you are being falsely accused, your freedom is our focus.


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