Understanding Field Sobriety Tests in Calgary
When a driver is suspected of impairment in Calgary, law enforcement officers often begin with standard field sobriety tests (SFSTs) before requesting a breath or blood sample. These roadside assessments are designed to evaluate coordination, balance, and attention — all of which can be impaired by alcohol or drugs.
Calgary Police Service officers typically use three tests:
- Walk-and-Turn (WAT): The individual is asked to walk heel-to-toe along a straight line and then turn and return the same way.
- One-Leg Stand (OLS): The person must balance on one leg while counting aloud for approximately 30 seconds.
- Horizontal Gaze Nystagmus (HGN): Officers track the movement of the eyes as the suspect follows a stimulus, such as a pen or flashlight.
These tests are used to establish reasonable grounds for further testing under the Criminal Code of Canada, such as a breathalyzer at the police station or a Drug Recognition Evaluation (DRE). However, SFST results alone are not definitive proof of impairment and may be open to legal scrutiny.
Legal Basis for Challenging Field Sobriety Tests in Alberta
In Alberta, the use of field sobriety tests (FSTs) is supported by the Criminal Code of Canada, particularly in cases involving suspected impaired driving due to alcohol or drugs. However, the law also places important limitations on how these tests are conducted and how their results can be used in court.
Under section 320.27 of the Criminal Code, a peace officer may demand that a driver perform standardized field sobriety tests (SFSTs) at the roadside if they have reasonable grounds to suspect impairment. The results of these tests can then lead to a demand for further testing, such as an Approved Screening Device (ASD) or Drug Recognition Evaluation (DRE).
However, these roadside assessments are screening tools—not evidentiary tools. This means:
- They are used to establish grounds for further investigation, not to prove impairment in court.
- Poor performance on an SFST is not conclusive evidence of guilt, especially when external factors like anxiety, fatigue, or medical conditions are involved.
A Calgary impaired driving lawyer may challenge the validity or interpretation of SFST results by:
- Questioning whether the officer was properly trained in administering the test
- Highlighting environmental factors (e.g., poor lighting, slippery road, uneven ground)
- Arguing that the officer failed to consider medical or physical conditions affecting performance
Courts in Alberta typically give limited weight to SFSTs unless they are supported by further testing. This opens the door for defence lawyers to dispute their accuracy or relevance—particularly if the accused’s Charter rights were violated during the stop or testing process.
Common Defences Used by Calgary Impaired Driving Lawyers
Challenging Officer Training and Administration of Tests
One of the most common defences involves questioning whether the arresting officer was properly trained to administer the Standardized Field Sobriety Tests (SFSTs). The SFSTs require precise procedures and instructions. Any deviation from the approved protocol—such as miscounting steps in the walk-and-turn or giving unclear instructions—can undermine the validity of the results.
In Alberta courts, a lawyer can request disclosure of the officer’s training records, cross-examine the officer’s credibility, and argue that improper testing renders the results unreliable.
Arguing Physical or Medical Limitations of the Accused
Field sobriety tests rely heavily on physical coordination, balance, and movement. Individuals with chronic injuries, vertigo, neurological disorders, age-related balance issues, or even recent surgeries may perform poorly—regardless of sobriety.
Calgary impaired driving lawyers often bring in medical records or expert testimony to demonstrate that their client’s test performance was affected by a legitimate health condition rather than intoxication.
Questioning Environmental Factors like Weather, Footwear, or Road Conditions
Roadside testing conditions in Calgary can be far from ideal. Icy or wet pavement, gravel shoulders, poor lighting, heavy wind, or uneven terrain can seriously affect test performance. So can inappropriate footwear like high heels or winter boots.
A defence lawyer may argue that external environmental factors made it difficult for any reasonable person to pass the tests, even if sober. Dashcam footage, weather reports, or officer body cam evidence can be introduced to support this line of defence.
The Role of Dashcam or Bodycam Footage in Calgary DUI Cases
Access to Calgary Police Bodycam Footage as Part of Disclosure
Under the Charter of Rights and Freedoms and Supreme Court rulings such as R. v. Stinchcombe, the Crown is legally required to provide full disclosure to the defence—including any video footage recorded at the time of the stop, arrest, and field sobriety testing. This includes:
- Body-worn camera (BWC) footage from officers
- Dashcam recordings from police vehicles
- Any CCTV or third-party recordings that may have captured the incident
A Calgary impaired driving lawyer can formally request this footage early in the legal process to verify the accuracy of the officer’s version of events.
How Visual Evidence Can Contradict Officer Testimony
Police reports may claim that a driver was swaying, slurring words, or failing to follow instructions. But video evidence sometimes tells a different story. A calm, cooperative driver who appears steady on their feet may strongly contradict claims of obvious impairment.
This can be used to:
- Challenge the officer’s observations
- Highlight inconsistencies or exaggerations
- Argue that the test was performed under unclear instructions or in inappropriate conditions
In some Calgary cases, video footage has led to charges being withdrawn after the Crown determined that the visual evidence undermined their case.
Importance of Video in Evaluating Test Conditions and Accuracy
Field sobriety tests are highly sensitive to context. Bodycam and dashcam recordings offer valuable insight into:
- Road surface (e.g., ice, snow, gravel)
- Lighting conditions at the scene
- Distractions like traffic noise or onlookers
- The accused’s footwear, clothing, and mobility
This context can validate or discredit the legitimacy of the roadside testing process. When combined with expert testimony, video footage may be key in proving that the results were unreliable or unfair.
Charter Rights and Field Sobriety Testing
Section 10(b) of the Charter: Right to Counsel upon Detention
Section 10(b) of the Canadian Charter of Rights and Freedoms guarantees that every individual has the right to retain and instruct counsel without delay upon arrest or detention. This right also includes being informed of this right by the police.
In the context of field sobriety testing in Calgary, this means:
- As soon as a driver is detained for the purpose of SFSTs, they must be informed of their right to speak with a lawyer.
- In many cases, failure to properly advise the individual at the roadside could be grounds for a Charter challenge.
Whether the Individual Was Properly Advised of Their Rights
A common defence strategy is to review whether the police officer:
- Clearly informed the driver they were being detained
- Told them about their right to speak with a lawyer
- Provided the opportunity to contact legal counsel as soon as practicable
If a Calgary impaired driving lawyer can show that this information was unclear, delayed, or withheld altogether, they may argue that the individual’s Charter rights were breached.
How Breaches in Rights Can Lead to Exclusion of Test Evidence
When there is a breach of Charter rights—especially the right to counsel—the defence may file a Charter application under section 24(2) to exclude the resulting evidence. If the court finds that the roadside tests (and possibly even subsequent breath or blood tests) were obtained following a Charter breach, they may rule that:
- The evidence is inadmissible
- The case against the accused is significantly weakened
- Charges may be reduced or even withdrawn
Why You Need a Calgary Impaired Driving Lawyer
How Local Legal Experience Helps Navigate Calgary Court Procedures
Every jurisdiction has its own courtroom culture and procedural nuances. A lawyer with local experience in Calgary’s Provincial Court and Court of King’s Bench understands:
- The typical practices of Crown prosecutors
- How certain judges interpret field sobriety evidence
- What documentation and motions are most effective in local impaired driving cases
A Calgary-based lawyer is also likely to be familiar with how Calgary Police Service officers conduct roadside tests, allowing for more strategic cross-examination and evidence review.
Importance of Early Legal Intervention to Preserve Defence Options
Time is critical in impaired driving cases. Engaging a lawyer immediately after being charged allows your legal team to:
- File timely Charter applications for rights breaches
- Obtain and review dashcam/bodycam disclosure
- Interview witnesses and gather weather or environmental evidence from the day of arrest
- Prepare for an Alberta Administrative Licence Suspension (AALS) appeal
The sooner you get legal help, the more options you’ll have to challenge the evidence and protect your driving privileges.
Selecting a Lawyer Familiar with DUI Trial Strategies and Police Protocol
Not all criminal lawyers are equally equipped to handle DUI cases. You need someone who:
- Specializes in impaired driving defence
- Has a strong understanding of field sobriety testing protocol and police training standards
- Knows how to use technical flaws, Charter arguments, and procedural errors to your advantage
A seasoned Calgary impaired driving lawyer can make the difference between a conviction and a successful defence. They’ll guide you through every step of the legal process — from first appearance to trial — and work toward the best possible outcome for your case.