Cannabis-related challenge to Canada’s impaired driving laws by man who killed mother and three daughters in violent crash has failed

Cannabis-related challenge to Canada’s impaired driving laws by man who killed mother and three daughters in violent crash has failed

An attempt to have Canada’s impaired driving laws labelled as unconstitutional by the man responsible for killing a Caledon mother and her three daughters in a violent car accident in Brampton last year has failed. 

Brady Robertson was behind the wheel of his Infiniti G35 In June 2020 with more than eight-times the legal limit of cannabis in his system when he sped through the intersection of Torbram Road and Countryside Drive in Brampton, slamming into the SUV carrying Karolina Ciasullo and her daughters. The collision sent the family vehicle crashing forward into a large concrete light standard that fell directly on the middle of the entire length of the vehicle, crushing it further. The girls were all under the age of 6. All four were killed in the collision. Robertson, 20 at the time, was taken to hospital with non-life threatening injuries. 

He was driving allegedly at about 167 kilometres per hour as he approached the intersection (according to police evidence, but the judge in the case has accepted some defence evidence refuting this estimated speed). He swerved out of control around a vehicle into the left hand turning lane before turning wildly back toward cars waiting at the lights, striking the Ciasullo SUV and crumpling the entire front third of his car.


Karolina Ciasullo with her three young daughters: six-year-old Klara; three-year-old Lilianna; and one-year-old Mila.

(Image from GoFundMe)


At the beginning of the case, Robertson pleaded guilty to four counts of dangerous operation of a motor vehicle causing death, and not guilty to four counts of impaired driving and a dangerous driving charge involving another reckless incident caught on video two days before the deadly collision. His lawyers alleged it was not possible to prove Robertson was the one driving the vehicle in the earlier incident caught on camera showing the same car riding onto a sidewalk as shocked passersby looked on. Two days later Robertson rammed the out-of-control vehicle into the white SUV, killing four members of the Ciasullo family. In November, the judge in the case, Justice Sandra Caponecchia, dismissed the arguments of the defence lawyer, agreeing with the Crown that Robertson was indeed the one behind the wheel two days prior to the fatal crash. 

Justice Caponecchia withheld judgement on the impaired charges until after the constitutional challenge was decided. Robertson’s lawyers claimed Canada’s impaired driving laws are “arbitrary and overboard” when it comes to THC, the active ingredient in cannabis. They argued it is too difficult to determine how THC impairs individuals with different levels of tolerance. 

The current legal limit is 5 nanograms per millilitre of blood, Robertson’s blood, according to a sample taken shortly after the accident, had eight times that amount.

In making her decision, Justice Caponecchia admits the question of impairment by THC raises “complicated policy considerations” but ultimately agreed that the laws regulating impaired driving as it relates to cannabis meet their intended purpose of detecting when an individual is impaired and deterring an individual from driving while impaired and therefore are not arbitrary or overbroad. 

The aftermath of the crash when Brady Robertson killed four members of the Ciasullo family.

(Image: Ontario Attorney General)


“I am satisfied that while the 5 ng/ml per se limit may impact some frequent and chronic users of cannabis, it does so in a way that does not violate the principles of fundamental justice because on balance, the impact is neither arbitrary, nor overbroad. The impact is consistent with Parliament’s stated intention when the possession of cannabis was legalized: to strengthen the laws with a view to not only detecting impaired drivers but also deterring individuals who consume cannabis from getting behind the wheel of a car when they represent a risk to the public,” Justice Caponecchia wrote.

Several experts testified about the impacts of THC on different individuals, with witnesses for the Crown and Robertson agreeing that cannabis will certainly impact an individual’s ability to drive, but “the extent to which it does so depends on the dosage, time of administration, pattern of use and experience with the drug.”

In making their case, lawyers for Robertson presented a series of hypothetical scenarios in an attempt to poke holes in Canada’s impaired driving laws. The judge accepted only one of these as plausibly illustrating a potential for a breach of Charter rights, that being the situation of a daily cannabis user. 

Brady Robertson will face sentencing later this month.

(Image from Facebook


“Both experts agree that studies show that habitual cannabis users can have 5ng/ml or more of residual THC after the impairing effects of the THC have worn off,” the judgement reads. The Crown’s expert stated that frequent users (4 or more times a week) will generally have residual THC levels that fall between 0 and 5 or 6 ng/ml.

This was still not enough to overturn the intent of the impaired driving legislation. 

“I am satisfied that the 5ng/ml per se limit was specifically put in place in anticipation of the legalization of cannabis with the objective to deter individuals who consume cannabis from getting behind the wheel of a car when they could represent a risk to the public. The preamble specifically declares that the new provisions were introduced to protect society and with deterrence in mind, and the Minister of Justice described the per se limits as representing a precautionary approach taken by government in preparation for the legalization of cannabis,” the judgement reads. “Based on the totality of factors I am entitled to consider; I am satisfied that the 5 ng/ml per se limit for THC had a dual purpose. The objective was to strength the pre-existing impaired driving laws and increase road safety by deterring cannabis users from getting behind the wheel of a car after having consumed cannabis.”

Justice Caponecchia has previously stated that the verdict on the impaired charges will rest on the outcome of the constitutional challenge, signalling Robertson will now be sentenced based on findings of guilt around those charges as well. 

According to MADD, sentencing for cases involving an impaired driver who kills others has to consider a number of factors. 

Anyone convicted who had two times the legal limit of a substance or less with no previous impairment charge and no criminal code traffic conviction within ten years, but pleaded not guilty should receive a minimum four to five year jail term and a lifetime driving ban.

Robertson had eight times the legal limit of THC, had driven violently appearing intoxicated in video footage just two days prior to killing the Ciasullos then denied he was the man shown in the video. 

Robertson was previously convicted for driving while suspended, careless driving and driving without a licence. He pleaded guilty in 2018 to threatening to damage property and possession of an unregistered firearm.

According to MADD, Robertson could face a 10 to 12-year jail sentence and a lifetime driving ban. 

In a high-profile case, Marco Muzzo was sentenced to ten years in prison following his 2016 guilty plea after being charged with four counts of impaired driving causing death and two of impaired driving causing bodily harm. He killed three children and their grandfather in 2015 when he was driving while impaired, speeding toward a remote Vaughan intersection where he struck their vehicle. He had about three times the legal limit of alcohol in his blood.

Submissions for Robertson’s sentencing will begin on April 25. 



Email: [email protected]

Twitter: @JoeljWittnebel 

COVID-19 is impacting all Canadians. At a time when vital public information is needed by everyone, The Pointer has taken down our paywall on all stories relating to the pandemic and those of public interest to ensure every resident of Brampton and Mississauga has access to the facts. For those who are able, we encourage you to consider a subscription. This will help us report on important public interest issues the community needs to know about now more than ever. You can register for a 30-day free trial HERE. Thereafter, The Pointer will charge $10 a month and you can cancel any time right on the website. Thank you

Submit a correction about this story