The Michigan State Police, in cooperation with local police departments, began a pilot roadside drug testing program on Nov. 8.


The program allows police to request that motorists suspected of driving under the influence of drugs submit to an oral fluid test. The mouth swab will test for cocaine, cannabis, heroin, methamphetamine, and prescription drugs.

Five counties are participating in the pilot program: Berrien, Delta, Kent, St. Clair, and Washtenaw. The program will not affect Hillsdale County.

The trial period for the program will go until Nov. 8, 2018. At that point, the Michigan State Police will have 90 days to analyze the program’s effectiveness and send a recommendation to the Michigan legislature about whether to expand or discontinue the program.

The program gets its authority from Public Acts 242 and 243, which Gov. Rick Snyder signed into law in 2016.

Special First Lt. for the Michigan State Police Jim Flegel said the Michigan State Police started the program in response to a 32 percent rise in drug-related traffic fatalities from 2015-2016.

“We’re hoping to give law enforcement another tool to assist them in detecting impaired drivers on controlled substances,” Flegel said. “If this program is successful after one year, then we will expand it to additional counties, and if it continues to be successful, I can foresee this program being implemented to all law enforcement agencies in Michigan.”

Flegel said the oral fluid pilot program is only a preliminary measure, just like a breathalyzer test. If the preliminary oral fluid test shows positive results, then officers can take suspects into the police department for a blood test, he said.

“If we can show the oral fluid is accurate, then it might not only be a preliminary test, but could also potentially be an evidentiary test,” he said.

Other law enforcement experts do not believe the oral fluid test is accurate enough to convict people of driving under the influence of drugs.

“There’s about a 25 percent false positive rate. So anything where the science can be 25 percent wrong, they shouldn’t be doing,” said Steve Miller, retired sergeant for the Canton Police Department. “The testing is not needed.”

Miller said officers should be able to determine whether someone is driving impaired without a test.

He also raised concerns about how the new law will affect medical cannabis patients.

“If an officer pulls a patient over, they’ll smell marijuana in the car, and then ask them to do a roadside swab test,” Miller said. “Well if you’re a medical marijuana patient, then you’re going to test positive.”

Miller said the positive test result does not necessarily indicate whether the medical cannabis patient has the mental and physical ability to drive. This is because the active drug in cannabis, THC, can remain in saliva for 24 hours or longer, even though THC only remains active for about an hour after consumption.

“Even though officers have no visible signs of impairment about the person, you’re gonna get people sucked into taking the test, which just like a portable breath test, is a civil infraction if you refuse to do it,” Miller said. “Our advice at the medical marijuana law firm is to not take the test. If they truly believe you’re under the influence of narcotics, they can still take you in.”

The fine for refusing to take the oral swab test is $200.

Frank Straub, director of strategic studies for the Police Foundation, said citizens, specifically medical marijuana patients, shouldn’t worried about being tested arbitrarily. He said officers must meet the same burden of proof to administer the preliminary oral fluid test as they do for the breathalyzer test.

“It can’t be the primary test out of the box,” Straub said. “Officers have to have reasonable suspicion to pull a car over to begin with. After having pulled someone over, they have to notice certain behaviors, at which point they can administer a field sobriety test. Based on the results of that field sobriety test, they then can request a breathalyzer or oral swab test.”

In response to the idea that medical cannabis patients will fail the oral fluid test, Straub said the test kit can be calibrated in such a way to differentiate “current use” from “residual markers” of cannabis consumption.

On top of these requirements, only specially trained officers, known as drug recognition experts, or DREs, have the authority to administer the preliminary oral fluid test, according to Flegel. There are 27 DREs working in the five participating counties.

Straub said people shouldn’t be fearful of driving due to marijuana legalization, but he also believes police officers should have the tools they need to address potential threats to public safety.

“I don’t know that we’ve necessarily seen dramatic increases in traffic-related fatalities as a result of marijuana legalization, but it is certainly something we need to be mindful of,” Straub said. “The focus is impaired driving, and so I think from that perspective, any steps that we can take to ensure the safety of people on our roads, the better off we are — within the parameters of the law and the Constitution.”

  • DrMichaelMilburn

    This “test” is a PR stunt–no meaningful data will be collected about its accuracy and reliability. No one should drive impaired, but actual impairment should be measured, and the level of impairment from cannabis that is criminalized should be the same as the level of impairment for the .08 blood alcohol level. How to measure impairment? Read on!

    I have developed a new public health app that measures actual impairment–it is called DRUID (an acronym for “DRiving Under the Influence of Drugs”) available now in the Apple App Store and in Google Play for the Android. DRUID measures reaction time, decision making, hand-eye coordination, time estimation and balance, and then statistically integrates hundreds of data points into an overall impairment score. DRUID takes just 2 minutes.

    Our website is

    DRUID allows cannabis users (or others who drink alcohol, use prescription drugs, etc.) to self-assess their own level of impairment and (hopefully) decide against driving if they are impaired. Prior to DRUID, there was no way for an individual to accurately assess their own level of impairment. DRUID also demonstrates that it is feasible to measure impairment reliably by the roadside, not just exposure to a drug. It could also be a way for cannabis users who have developed tolerance to show they are unimpaired.

    DRUID was featured on NPR’s All Things Considered:

    Also on television:

    After obtaining my Ph.D. at Harvard, I have been a professor of psychology at UMass/Boston for the past 40 years, specializing in research methods, measurement and statistics.

    Michael Milburn, Professor
    Department of Psychology