We are days away from the legalization of cannabis in Canada. It is happening on October 17. There are so many aspects of life that seem affected. Students and employees are signing on to updated school or workplace policies on marijuana use. Travellers are wondering if they will have trouble crossing the U.S. border. Investors are looking at putting money into cannabis companies. The Georgia Straight even has an entire website devoted to cannabis.

We are days away from the legalization of cannabis in Canada. It is happening on October 17. There are so many aspects of life that seem affected. Students and employees are signing on to updated school or workplace policies on marijuana use. Travellers are wondering if they will have trouble crossing the U.S. border. Investors are looking at putting money into cannabis companies. The Georgia Straight even has an entire website devoted to cannabis.

Of course, health and public safety is a common concern with the upcoming legalization. One particular concern is road safety and impaired driving. The new laws and regulations set out maximum allowable THC levels to address this risk. These limits are to promote public safety from a criminal-law standpoint.

That said, impaired driving can be an issue without becoming a criminal matter. Driving on our roads already has its own risks. Couple that with the physiological effects of marijuana and you’ll see another arena where this issue will be raised: personal-injury lawsuits.

Previously, I addressed how medical marijuana is relevant in personal injury lawsuits. In some instances, the courts have accepted medical marijuana as a form of treatment. In doing so, the courts can award damages that cover those expenses.

These personal-injury lawsuits, such as those stemming from car accidents, typically involve acts of negligence. Determining whether or not someone was negligent can be another issue where cannabis is relevant.

So, does driving under the influence of marijuana amount to negligence?

The short answer is: not necessarily. The mere use of cannabis, in itself, does not equate to negligence. It’s just not that simple. That’s because negligence, in law, has a special meaning. First, you need a situation where a person has a legal duty to take reasonable care to avoid foreseeable harm to others. Second, that person fails to meet this duty. Third, there is harm caused from this failure to meet the duty. If you have these elements, you have negligence. And when someone is negligent, they are legally responsible for the damages and losses caused.

How does cannabis factor into a car accident where both drivers blame each other? Just because one driver was using cannabis doesn’t mean that person was negligent. An important question in determining negligence where cannabis is considered is causation. Did the cannabis use actually cause or contribute to the accident?

Let’s go through an exercise to show how this works. Let’s say that around midnight, a person smokes marijuana. At 2 a.m., that person gets into a car and heads southbound through an intersection with a green light. Approaching this intersection, heading northwest, is a police cruiser with its lights flashing and siren blaring. The officer is responding to an emergency call and is going way beyond the speed limit. The cruiser entered the intersection on a red light and struck the other car. Tragically, it’s a serious accident with multiple fatalities. This was the exact scenario before the courts just a few years ago. So, who was negligent here: the impaired driver or the speeding officer?

The court factored in the red light for the officer, the police cruiser’s speed, and the poor visibility at this intersection. It found that the officer was negligent by not exercising the care required of a reasonable police officer. But what about the driver who smoked marijuana? Was there a sharing of blame?

The court considered the driver’s marijuana use and its impact on reaction time. A toxicologist gave evidence that the driver was impaired but the toxicologist could not say what exact impact the THC levels had on this person.

Which brings us back to causation. Did marijuana actually cause or contribute to the accident? Without evidence on the marijuana’s actual impact on this driver, the court did not think so here. The court felt a sober driver would not have avoided the police cruiser either. As a result, the driver was absolved of all blame and the fault rested entirely with the officer.

To be clear, the court was not endorsing impaired driving. It was not suggesting that impaired driving would be overlooked or excused. It was making a decision of negligence for a particular set of facts and evidence. With different facts or evidence, the court could just have easily found the impaired driver negligent. That’s why you can’t take this decision to mean that you can get away with driving after cannabis use.

And if you need another reason to drive sober, it’s this: impaired driving may violate the terms of your insurance policy. Your insurance coverage may be revoked when you need it the most.

When determining the fault for a car accident, cannabis use would be viewed in the same way as other reckless behaviours, like drunk-driving or text-messaging. Such behaviours would be looked at closely for cause and effect leading up to the accident. Regardless of whether it helped cause an accident, these risky behaviours can lead to disastrous consequences for everyone. Impaired driving is dangerous; plain and simple.

In fact, the impaired driver from that court decision died in the accident.

A word of caution: you should not act or rely on the information provided in this column. It is not legal advice. To ensure your interests are protected, retain or formally seek advice from a lawyer. The author’s opinions of the case are based on the court’s published reasons and not on any firsthand knowledge of the lawsuit or its parties.