OTTAWA – The first device set to be approved by the federal government for roadside saliva tests to determine marijuana impairment isn’t suited for cold weather, and has been found to give “fairly large proportions of false-positive or false-negative results.”

Last month Justice Minister Jody Wilson-Raybould published a notice of intention to approve the Dräger DrugTest 5000, and list it as “approved drug screening equipment” for law enforcement to use at the roadside to test for both THC and cocaine.

However, CTV News has found concerns about the efficacy and efficiency of the device.

“It’s inevitable that we’re going to see constitutional challenges as soon as this device hits the roads. This is something that is a significant departure from what the Supreme Court of Canada has authorized, and what police has been doing thus far,” said Kyla Lee, a criminal lawyer focused on roadside impairment testing.

A study published earlier this year in the Journal of Analytical Toxicology examining the use of the device in Norway shows that the Dräger DrugTest 5000 “did not absolutely correctly identify DUID (driving under the influence of drugs) offenders due to fairly large proportions of false-positive or false-negative results compared to drug concentrations in blood.”

The study included over 300 Norwegian drivers who were tested for impairment using both the oral device as well as a blood sample. It found that the proportion of false-positive results generated by the device compared to the finding of a blood sample was 14.5 per cent for cannabis, and 87.1 per cent for cocaine.

As well, compared to drivers whose blood samples showed their THC levels were above the legal limit, 13.5 per cent of drivers showed false-negatives, meaning the THC in their system was not detected by the oral screen.

The study’s authors said that the Norwegian Mobile Police— who have been using the device since 2015— claim it was “still a valuable tool in identifying possible DUID offenders, resulting in more than doubling the number of apprehended DUID offenders.”

The device has also been used in Australia, where police admitted in 2016 that it gave accurate results only about two thirds of the time.

Canadian climate too cold?

There are also questions about the suitability of the Dräger DrugTest 5000 for the Canadian climate, with the device’s operating temperature ranging between four and 40 degrees Celsius.

“A lot of Canada most of the year is below those temperatures, and so you’re going to see tests either taken in unreliable circumstances, or a device that’s completely unworkable for the police a good majority of the year,” Lee said.

The tests have also been found to be time consuming, requiring the police officer to orally swab the driver for up to four minutes, and it can take as long as ten minutes to test the sample.

The test also requires there not be any food or drink in the subject’s mouth for 10 minutes prior to taking the test. All told, Lee estimates each test will take up to half an hour to complete on the roadside, which she said is 10 times as long as a breathalyzer test for alcohol detection.

"What you're going to be doing is seeing people detained for lengthy periods of time at the roadside with no opportunity to contact lawyers,” said Lee.

In a statement to CTV News, Managing Director of Dräger Canada Rob Clark said the company is “proud” to have its device considered for approved use by Canadian law enforcement.

“Dräger has 60 years of experience in roadside detection, and our technology has been consistently chosen by law enforcement around the world who trust its track record of reliability and accuracy,” he said, adding that the company is looking forward to working closely with Canadian police officers to help make roads safer.

The authorization to use these kinds of devices came as part of Bill C-46, the impaired driving legislation that passed along Bill C-45, the Cannabis Act, which sets up the legal regime for recreational marijuana.

Bill C-46 changed impaired driving laws to give police new powers to conduct roadside intoxication tests, including oral fluid drug tests, and makes it illegal to drive within two hours of being over the legal limit.

The bill specifically created three new criminal offences related to driving with blood concentration between two and five nanograms of THC—the primary psychoactive ingredient in cannabis—per milliliter of blood within two hours of driving.

Throughout the parliamentary study of the legislation, a dominating question was the efficacy of determining cannabis impairment. Experts have said that determining what amount is required to actually constitute impairment, and how long TCH can linger in a person’s system largely depends on the individual and their tolerance.

Speaking to these testing devices generally, criminal defence lawyer Solomon Friedman told CTV News that the science is “unproven,” and it’s sparking concern that the devices are being rushed out without enough of an opportunity to test their reliability, given the concerns being raised in other jurisdictions.

“The legislation assumes as fact that the results that are obtained from these machines are accurate, so the burden of proof is going to rest very squarely on the individual accused and their counsel to overturn the scientific results of these machines,” said Friedman.

Positive test the first step

In the July 19 notice from Wilson-Raybould, it states that a positive result obtained by the Dräger device “would be a strong indication of recent use.” If the oral fluid sample tests positive, it would provide the grounds, combined with an officer’s other observations, to proceed further and demand a formal drug recognition evaluation, or a blood sample.

Under Bill C-46, officers need reasonable suspicion that there are drugs in a driver’s system before pulling them over and testing them, though if the person fails the roadside oral test, the person will be arrested and taken in for additional testing.

Failing an oral roadside test is not a criminal offence, nor can the results be used in court. A blood test is required to determine legal impairment.

The notice for Dräger DrugTest’s approval comes after toxicologists and traffic safety experts on the Drugs and Driving Committee of the Canadian Society of Forensic Science—an independent adviser to the Justice Department— studied the device.

Those interested have a 30-day window from the notice’s posting to contact the Justice Department with their feedback.

In a statement to CTV News, Scott Bardsley, spokesperson for Public Safety Minister Ralph Goodale, said Public Safety Canada and the RCMP conducted a pilot project between December 2016 and March 2017 with several law enforcement agencies across Canada to test officers’ ability to use roadside testing devices under different weather conditions.

The pilot used two oral screening devices, though this specific device was not one of them.

The federal government is providing $81 million for provinces and territories to train officers and purchase screening devices, though it won’t be mandatory for agencies to use the drug detection device.

As of May, the Canadian Association of Chiefs of Police told The Canadian Press that just 773 officers across the country have received specialized drug recognition training.

StatsCan: 4.6M people drive high

A new statistics Canada survey released Thursday shows that 14 per cent of cannabis users with a driver’s license have gotten behind the wheel within two hours of using the drug.

About 1.4 million Canadians reported that they had been a passenger in a vehicle driven by someone who had consumed cannabis within the last two hours.

The survey also reported that in the second quarter of 2018, in which the results were harvested, 4.6 million Canadians aged 15 or older reported using cannabis in the three months prior.

MADD Canada’s Steve Sullivan told CTV News that he expects the rate of drug-impaired driving will decrease once the drug-testing devices are in use.

It is possible additional devices could be approved by the federal government, giving police agencies the choice in which they decide to employ, if they elect to add saliva tests to their roadside arsenal at all.

The notice for approval explicitly states that the use of the Dräger device will not be mandatory.

Police already enforce drug-impaired driving laws using Standard Field Sobriety Testing, which does not require these devices.

Recreational marijuana becomes legal in Canada on Oct. 17.

With files from CTV News’ Senior Political Correspondent Glen McGregor and CTV Ottawa