Nearlyhalf of Americansbelieve police can’t detect recent cannabis use behind the wheel, but new roadside technology may soon prove them wrong.

Minnesota Department of Public Safety (DPS) officials are now pushing lawmakers to make oral fluid testing tools as common as breathalyzers, following a successful pilot program.

The $900,000 pilot project was part of the state’s Cannabis Legalization Act, which made recreational cannabis legal in 2023. The goal was to help officers screen drivers for impairing substances on the side of the road. While the project came out of the state’s move to illegalize recreational cannabis, the tools test for several different drugs, including opiates, cocaine and methamphetamines.

After comparing 329 roadside oral fluid, or “spit” tests with state crime lab results, DPS officials are confident: The technology works.

“These are good, solid tools,” state Office of Traffic Safety (OTS) Director Mike Hanson said at a recent press conference. OTS is within DPS.

Minnesota Department of Public Safety

The intention is not for the results from the roadside tests to be used in court, but rather, as a preliminary testing method in which a positive drug test would generate probable cause so that a judge would have enough evidence to sign a search warrant that would lead to a blood and urine test to be completed at the state’s lab. The data from the lab tests is what could be used in criminal prosecution.

The goal of the roadside tech is simply to give officers a tool to understand what they’re working with in the moment to guide the future course of action.

“To help the officer identify that somebody is impaired and what they’re likely impaired by,” Hanson said.

As part of the pilot, trained drug recognition experts were given saliva testing kits from two different companies, the Abbott SoToxa™ Oral Fluid Mobile Test System and Dräger DrugTest 5000.

Government Technology dug into the data in the report released to the state Legislature, uncovering some limitations to the tech, as well as a clear preference from polled law enforcement agents between devices.

DOES ROADSIDE CANNABIS TESTING WORK?

In the pilot, officers collected roadside spit tests, with lab-based blood or urine samples taken in most cases for comparison. Lab results detected drugs 808 times, compared to 554 for the roadside tests — an 82 percent average match. However, the state lab’s broader testing panel often identified substances the roadside devices missed, as detailed in the chart below.

The chart reveals a clear trend: Lab results detected more drugs than roadside spit tests, with the exception of methamphetamine, potentially due to false positives from medication cross-reactivity. Roadside tests performed best with amphetamine, cocaine, opiates and cannabinoids, but struggled with benzodiazepines (22 percent match) likely due to oral fluid limitations.

Additionally, the roadside devices don’t test for fentanyl, which the lab detected 69 times.

HOW DID THE ROADSIDE TESTING TECH COMPARE?

The pilot compared two devices: SoToxa™ and Dräger. In 13 instances, SoToxa™ detected drugs missed by Dräger, among 61 subjects tested with both devices.

Officer surveys revealed a strong SoToxa™ preference, particularly for size and portability, as shown above. When asked for their overall preference, 83 percent of officers preferred SoToxa™. DPS is recommending legislators approve both instruments as preliminary screening devices, allowing officers to choose which device they prefer.

WHY IS THIS TECH IMPORTANT?

The AAA Foundation for Traffic Safety conducted asurveyof drivers that revealed only about 1 in 5 drivers felt their driving was worse after use, while 34 percent thought their driving improved after using cannabis.

However, that’s not what some public safety officers witness on the roads.

“I’ve had some people with wildly accelerated or wildly delayed perceptions of time, which obviously when you’re driving down the freeway or passing crosswalks, that’s a huge problem,” Officer Jake Cree from the Blaine Police Department said during the state’s news conference about the pilot.

While the pilot gave the state an opportunity to see how the roadside technology performed, it also gave officials valuable, and eye-opening, data about the state of impairment on the roads that they’re calling a “multiple-substance impaired driving crisis.”

DPS pilot data revealed that 62 percent of drivers had more than one drug in their system at the time of the test, and in one case a driver tested positive for six drugs. Additionally, 90 percent of drivers who tested positive for alcohol also tested positive for one or more drugs.

Now, DPS would like to see the devices become as common as breathalyzers, to be used in the same way law enforcement officers evaluate somebody under the influence of alcohol. The state’s push to equip officers with these $5,000 devices, with tests costing $25-$30 each, signals a potential shift in enforcement around people driving while impaired.

While the pilot put the tools in the hands of specially trained drug recognition experts (DREs), DPS officials believe they have a more useful purpose in the hands of officers without that specialized training, to determine the best next steps.

“The DREs have a high level of training, so they aren’t the ones necessarily that will need to have this type of instrument to confirm what they’re observing,” said Hanson. “But the average street officer out there may not have that high level of training, and this is just another tool they can use to reach that arrest or no arrest decision.”