A person’s breath or blood samples are crucial evidence in proving charges of impaired driving and ‘over 80’. Also, the timeliness in collecting this evidence is relevant in determining a driver’s blood alcohol concentration (BAC) at the exact time the accident occurred. If the process to take a breath or blood sample from an accused person is delayed or does not follow proper procedures, then defence can raise concerns about the validity of this evidence and whether the accused’s rights were breached under the Charter of Rights and Freedoms.

In cases where a driver was injured in a collision and immediately taken to hospital, it can be more difficult for officers to control the process of taking breath or blood samples, but arresting officers are still under the same legal obligation to ensure that required procedures are followed. Blood and breath tests may be delayed when medical treatment is the first priority for an injured driver; yet, without a breath test at the scene, it is difficult for a toxicologist to draw defensible conclusions about a driver’s blood alcohol concentration at the time of the accident. For example, in a situation where a driver may be affected by bolus drinking because they consumed a significant amount of alcohol immediately prior to the collision, defense counsel may argue that the alcohol was not yet absorbed at the time of the accident. These issues were raised in a 2015 trial, R. v. Pyrek, and directly affected whether the charges of impaired driving and ‘over 80’ could be proven by the Crown. 

The R. v. Pyrek Case

The trial arose when a driver lost control of his vehicle and hit a tree, injuring himself and his passenger. The two were on their way to a McDonalds in Mississauga, having left a party where they had been playing ‘beer pong’ (a drinking game) shortly before leaving. The car was entirely destroyed, and firefighters were the first on the scene and extracted the two occupants from the vehicle. Police arrived in time to trail the ambulance transporting the two accident victims to Credit Valley Hospital. There was no time for police to consider or assess whether the driver may have been impaired at the scene.

At the hospital, the arresting officer did not see the injured driver until after he received medical attention. The officer was in the patient’s room when blood samples, in the form of vials, were taken by a nurse for the purpose of medical treatment but he did not follow where the blood went, nor did he see it labeled. After speaking to the injured man, the officer noticed the smell of alcohol on his breath, red and watery eyes and somewhat slurred speech, and concluded that the driver’s ability to operate a motor vehicle was impaired by alcohol. As a result, he charged the man with impaired driving, read him his rights to counsel and the caution, and made a breath demand. The officer testified that the driver said he did not want to call a lawyer and also agreed to the breath demand.

The arresting officer assumed the breath technician would obtain a warrant for the blood sample, but when the breath technician arrived some time later to administer the breath test, the technician did not discuss a warrant with hospital staff. The breath technician testified that he did not notice slurred speech when he made the breath demand and admitted that bloodshot eyes could have been caused equally by allergies as alcohol consumption. When the breath technician took the accused’s first breath sample, it was about 4 ½ hours since the accident and at this time, the Intoxilyzer 8000 C registered 51 mg of alcohol in 100 ml of blood. A second breath sample was not taken because hospital staff decided to transfer the injured man to Sunnybrook hospital immediately, as his condition had worsened.

In the hospital lab, the breath technician asked for a vial of the patient’s blood which was identified by the patient’s name; then it was sealed and left in the lab. A warrant to obtain the driver’s blood sample was not obtained and authorized until almost one month after the accident, at which time the arresting officer went to Credit Valley Hospital and seized the blood sample. Subsequent testing of the blood found a blood alcohol reading of 107 mg of alcohol in 100 ml of blood.

Witness testimony included statements from several friends who attended the party, as well as the accused man and his passenger, who testified that there was drinking taking place until immediately before their departure from the party, and at a minimum, the driver consumed a bottle of beer and a glass of wine within a short time before getting behind the wheel. Further relevant testimony was that of the hospital medical technologists, none of whom observed the chain of evidence from the patient’s room to the lab; and all agreed that although there was no evidence to indicate that the accused’s blood samples were incorrectly labelled, there have been instances of incorrect labelling of vials in the past. 

Analysis and Findings

In the Pyrek trial, the accused faced charges of impaired operation of a vehicle causing bodily harm and ‘over 80’ resulting in bodily harm. Defence counsel brought an application to exclude the defendant’s blood samples obtained pursuant to the search warrant issued one month later, charging that the blood was obtained contrary to section 8 of the Charter.

Some of the key factual and legal issues, in this case, were as follows:

  1. Has the Crown proven continuity and chain of custody with respect to the blood?
  2. If affirmative, was there a Charter violation in obtaining the blood samples, and if so, should the blood samples be excluded as evidence?
  3. Did the Crown successfully prove the underlying assumptions in the toxicologist’s report?
  4. Based on the above decisions, has the Crown proved, beyond a reasonable doubt, that the accused operated a vehicle with a blood concentration exceeding .08?
  5. Has the Crown proved impaired driving beyond a reasonable doubt?

Defence counsel argued that the continuity of the blood taken from the accused had not been established, in terms of whether the court could be assured that the same blood drawn from the accused is the blood that was tested, without the potential for mislabeling or contamination. However, this argument was rejected, in part due to the lab technologists’ testimony that there were no reports of a concern with the labelling of the defendant’s blood. 

Charter Rights Violation Argument

Regarding the defence’s assertion that there was a violation of the accused’s Charter rights in the taking of the blood samples, the following argument was presented. The hospital’s normal practice is to keep blood samples for a maximum of 5 days before destroying them, but in this case, the defendant’s blood was kept for 30 days until a search warrant was obtained. The defence argued that the hospital was acting as an agent for the police during the 25 days the blood was being held, and this constitutes an unreasonable seizure contrary to the Charter. Defence counsel added that the defendant should reasonably expect that his blood samples would be disposed of after 5 days, as was normal practice for the hospital. The breath technician testified that when he sealed the blood sample in the lab, he informed hospital staff that they could use the sample for medical purposes if they so needed, but would have to inform police if they did so. The judge did not believe that hospital staff understood the legal implications of the seal on the vial, in terms of their freedom to use the blood; nevertheless, it was concluded that keeping the blood, by medical professionals, past the time it is normally disposed of, does not constitute an unreasonable seizure contrary to section 8 of the Charter, and therefore, the blood sample was deemed admissible.

The toxicologist testified that based on the defendant’s blood alcohol concentration at the time his blood sample was tested at the hospital, the defendant’s ability to operate a motor vehicle was impaired at the time the accident occurred. This testimony was based on several assumptions pertaining to the timing of the alcohol consumption, the rate of drinking, and an understanding of the rate of elimination of alcohol from a person’s blood. However, the toxicologist’s report assumed that there was no consumption of large amounts of alcohol within approximately 15 minutes of the accident, which is sometimes called the “no bolus drinking” assumption. 

Bolus Drinking Effects

The effect of bolus drinking is described as a situation where the accused driver’s BAC at the time of an accident is actually below 80 mg of alcohol in 100 ml of blood because it has not yet been fully absorbed and is still on the rise. In this situation, BAC registers as much higher an hour or more later. The judge accepted that the accused was not ‘drinking at a normal pace’ and may have easily consumed both a glass of wine and beer in the 15 minutes prior to the accident. Consequently, the judge concluded that evidence supported the likely occurrence of ‘bolus drinking’ and thus, he gave no weight to the toxicologist’s report. 


Without the toxicologist’s report, the judge’s conclusion was that the evidence does not prove, beyond a reasonable doubt, that the defendant’s driving was impaired by alcohol. Accordingly, the defendant was acquitted on both charges: ‘over 80’ and impaired driving.

By Published On: August 15, 2023Last Updated: August 15, 2023Categories: Impaired Driving/DUI

Contact Us

Complete the form below to get a free meeting and quote.

Protected By Google reCAPTCHA | Privacy - Terms