Roadside testing for cannabis impairment has been a growing concern since the introduction of Bill C-46 which passed in June to amend the Criminal Code for the Impaired Driving Act.
According to C-46, law enforcement can demand a mandatory alcohol screening without suspecting the driver of drinking, although grounds for suspicion will still be necessary to demand roadside drug testing.
There are constitutional concerns regarding the new legislation, particularly when it comes to screening for cannabis.
On July 19, the Minister of Justice and Attorney General Jody Wilson-Raybould gave notice of her intention to approve the Dräger DrugTest® 5000 STK-CA which uses saliva to screen for seven types of drugs, including THC.
A 2016 study published in the Canadian Society of Forensic Science Journal examined oral fluid drug screening devices and found that they “could prove to be a valuable tool in the detection of driver drug use in Canada.”
While the researches cited being optimistic about the use of saliva screening, the discussion also noted that a Drug Evaluation and Classification Program (DECP) would still be necessary to evaluate impairment.
In 2017, Public Safety Canda, in collaboration with the RCMP and Canadian Council of Motor Transport Administrators, published a report on an oral fluid drug screening device pilot project.
The project did not evaluate the reliability of the devices, citing that the 2016 study demonstrated adequate efficacy. Instead, the objective was to determine whether the devices would function in the often-harsh Canadian climate.
Malfunctions did not proportionately increase in extreme weather conditions but “proportionally, tests conducted outside of suggested operating temperatures were more likely to produce drug-positive results.”
The report recommended “further research on the reliability of devices used outside of standard operating temperatures.”
Perhaps the greatest issue with saliva-based drug testing is “that presence of a drug in the oral fluid does not imply impairment,” as stated in the report.
Per se limits have been introduced that do not coincide with impairment, and are also tied to severe punishments:
“With alcohol, we can say a person is impaired when they reach a certain level,” criminal defence lawyer Sarah Leamon previously told Daily Hive. “A person doesn’t have to be displaying that they’re impaired; if they have that amount of alcohol in their bloodstream then they are.”
Leamon added that there “is no correlation between levels of THC in system and impairment,” a concern that is echoed by Dr. Tony George, a researcher at CAMH and professor at the University of Toronto.
Dr. George previously spoke with Daily Hive and said that one of the issues with reliable roadside testing is that people develop a tolerance to cannabis, and of equal concern is that you can test positive for THC even if you’re sober.
THC is fat soluble and therefore stays in your body for much longer than alcohol, which can dissipate in hours.
“I don’t understand how this framework is [quantifying] impairment when I’m saying clinically if we can’t detect cannabis in someone’s urine at levels at less than 20, we call that abstinence,” said Dr. George.
The public comment period will be open until August 18, at which point the Minister “will take into consideration the advice of the Drugs and Driving Committee (DDC) of the Canadian Society of Forensic Science and any public comments received and will make a final decision on whether to approve (by Ministerial Order) this drug screener for use by law enforcement,” a representative from the Department of Justice Canada told Daily Hive via email.
According to the rep, “the DDC is continuing to evaluate other drug screeners for use by law enforcement. If they meet the evaluation standards of the DDC, they may be recommended for the Minister’s consideration in future.”
Once approved, law enforcement would be able to use the drug screener as a drug detection tool in addition to a Standard Field Sobriety Testing (SFST) and Drug Recognition and Evaluation (DRE).
To submit a comment to the Minister on the subject, email [email protected].
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