House Bill 5024 would authorize a commission to study and recommend a THC limit that would constitute impaired driving, much like the .08 blood alcohol content established as a threshold for drunken driving. THC is the component responsible for marijuana’s effects.
The law shields medical marijuana patients from prosecution for drugged driving as long as they aren’t under the influence of marijuana, but there’s no blood level threshold defining what constitutes “under the influence.”
Lucido said the study is meant to find ways to protect both medical marijuana patients and the general public.
“I’m really targeting the medical marijuana cardholders — if you’re going to smoke, I don’t care,” Lucido said. “Do what you do best and take care of your health, but don’t jeopardize yourself or others on the road with a piece of equipment that kills.”
In a news release Tuesday, the AAA Foundation for Traffic Safety said a comprehensive approach to recognizing drugged driving was needed, noting a study that found fatal crashes involving drivers who’d recently used marijuana doubled in Washington after the drug was legalized.
But a traditional blood test — a measure of nanograms per milliliter of blood — may not work as a good gauge in the case of marijuana use, Kevin Bakewell, senior vice president and chief public affairs officer for AAA, said in a statement.
“There is understandably a strong desire by both lawmakers and the public to create legal limits for marijuana impairment, in the same manner as we do with alcohol,” Bakewell said in an emailed statement.
“In the case of marijuana, this approach is flawed and not supported by scientific research. It’s simply not possible today to determine whether a driver is impaired based solely on the amount of the drug in their body.”
The foundation said legal blood limits are problematic because THC may appear in a person’s system long after its effects disappear, high THC levels may drop below legal thresholds before a warrant can be secured for a blood test, and the same THC level may produce different effects based on the person, strain, and term of use.
The foundation instead encouraged the development of a system that included a positive test for recent marijuana use and one that gauged marijuana use based on behavioral and physiological evidence.
Lucido said all of those variances will be taken into account by the commission the bill would create. According to the bill summary, the commission would include a representative from the Michigan State Police, a medical doctor, forensic toxicologist, medical marijuana patient and a professor from three different Michigan public research universities.
“We’re going to have a thorough investigation and vet out all the problems that may arise from this,” Lucido said.
Matt Newburg, a marijuana defense lawyer representing some defendants in St. Clair County, was doubtful that a reliable blood level threshold could be determined as the drug functions differently than alcohol.
“They can’t fix the number of nanograms of THC in a person’s system and correlate that to their ability to drive a vehicle,” Newburg said.
“My concern is that they create some unreliable threshold that is not going to pass muster in the court.”
St. Clair County Prosecutor Mike Wendling said while an established blood level threshold of marijuana would be helpful, its not essential to proving any case of operating under the influence.
“Even alcohol, it’s not just based on a quantifiable level,” Wendling said.
He said officers are trained to recognize various signs for drunken or drugged driving before a blood test is ever taken.
“The nanogram level or the amount of marijuana in a person’s system would just be a factor,” Wendling said.
“That information would be relevant to a judge or jury’s determination in level of impairment, but it still would be coupled with many factors.”
Contact Beth LeBlanc at (810) 989-6259, firstname.lastname@example.org, or on Twitter @THBethLeBlanc.