LAST WEEK, the Michigan Supreme Court ruled that the Michigan Medical Marihuana Act (MMMA) protects registered patients while driving with THC in their bloodstreams, although it left open the possibility of prosecution for impaired driving.
In the case of People v. Koon, the court ruled unanimously (and without oral argument):
“This case requires us to decide whether the MMMA’s protection supersedes the Michigan Vehicle Code’s prohibition and allows a registered patient to drive when he or she has indications of marijuana in his or her system, but is not otherwise under the influence of marijuana. We conclude that it does.”
The case originated in Grand Traverse County in 2010 when defendant Rodney Koon was stopped for speeding. The police report states that Koon voluntarily produced a pipe, acknowledged he was a medical marijuana patient and admitted to having smoked several hours earlier.
A blood test verified the presence of THC in his blood and he was charged with operating a motor vehicle with the presence of a schedule 1 controlled substance in his body. Under Michigan’s Zero Tolerance Law, the statute provides that driving with any amount of THC in your blood is illegal. The local court ruled in Koon’s favor but subsequent appeals by prosecutors ruled against him.
The Supreme Court didn’t even bother to take up the appeal from Koon’s lawyer. It just struck down the Court of Appeals ruling as out of hand. This is a big win for medical marijuana supporters. Some prosecutors had derived the strategy that since Michigan law says it is illegal to drive with any amount of THC in your system, it is possible to prosecute drivers even if they are registered patients and don’t exhibit any signs of intoxication. But the state high court ruling reads:
“While we need not set exact parameters of when a person is ‘under the influence’ we conclude that it contemplates something more than having any amount of marijuana in one’s system and requires some effect on the person.”
This means that prosecutors have to establish that a driver was “impaired” rather than just having “internal possession” of marijuana. Furthermore, the court called on the Legislature to define what is defined as legally impaired:
“As the Legislature contemplates amendments to the MMMA, and to the extent it wishes to clarify the specific circumstances under which a registered patient is per se “under the influence” of marijuana, it might consider adopting a “legal limit,” like that applicable to alcohol, establishing when a registered patient is outside the MMMA’s protection.”
A recent FOX News telephone poll found that 85 percent of Americans believe medical marijuana should be legal. As marijuana is step-by-step legalized across the country, medical or otherwise, states are struggling with all kinds of issues about how to handle it.
One of the most contentious issues is how to determine what level of THC in a driver’s blood indicates impairment — presupposing that impairment can even be determined in that way.
In Colorado, where voters legalized marijuana last November, the legislature recently passed a law setting five nanograms of THC per milliliter of blood or higher a sufficient cause to ticket a person for impaired driving. However, drivers can defend themselves by arguing they were not too impaired to drive. Pro-marijuana activists who believe a “per se” THC blood level is not an accurate or definitive indicator of impairment for drivers generally support this line of thought.
“Law enforcement has a number of tools at their disposal to identify drivers who may be under the influence of alcohol or drugs,” says Paul Armentano, deputy director of the National Organization for the Reform of Marijuana Laws, who testifies as an expert witness in legal cases on the science of marijuana. “In my opinion, there is an overreliance in criminal prosecutions on the presence or quantity of THC in the blood. There is an assumption that when THC is present in the blood at a certain level that one can definitively infer impaired performance. That is not the case.”
Washington state has also established the 5 ng/ml level, and there has been talk in the Michigan Legislature about establishing the same standard. But Armentano and others say that numerous other things should be taken into account, such as the officer’s report, the suspect’s behavior at the scene, the driving behavior that resulted in the pull-over, drug toxicology testing, drug recognition evaluation and sobriety testing at the scene — like standing on one leg, walking and turning, the Rhomberg stationary balance test and other measures.
The National Highway Traffic Safety Administration seems to agree with them. On the NHTSA Drugs and Human Performance Facts Sheets, it reads, “It is difficult to establish a relationship between a person’s THC blood or plasma concentration and performance-impairing effects. … It is inadvisable to try and predict effects based on blood THC concentrations alone …”
In addition, there are studies showing that “experienced” marijuana users are better drivers after having smoked marijuana than newbies. Marijuana smokers tend to be conscious that they are high and compensate by driving more slowly, as opposed to alcohol drinkers who tend to not realize they are drunk and have few inhibitions about their driving behavior.
One study, published in the journal Psychopharmacology in 2010, concluded that, “Alcohol significantly impaired critical tracking, divided attention, and stop-signal performance. THC generally did not affect task performance. … [T]he present study generally confirms that heavy cannabis users develop tolerance to the impairing effects of THC on neurocognitive task performance.”
Much more is known about alcohol intoxication than marijuana intoxication and a 0.08 percent blood-alcohol level is fairly standard for establishing impairment. But even that is in flux. There have been recent calls to lower that level to 0.05 percent. Whatever the percentage, alcohol is processed differently by our bodies than THC and other cannabinoids. Most alcohol is absorbed into the body through the small intestine and speed of intoxication is dependent on variables such as how much food is in the stomach and body weight.
THC binds to cannabinoid receptors in the brain. The THC blood level peaks in marijuana users within five to 10 minutes after smoking — it takes much longer when it’s eaten. Generally, the level drops to under 5 ng/ml within a few hours. This is dependent on factors such as the potency of the marijuana smoked and how often the person smokes marijuana.
So-called chronic users may test over 5 ng/ml at all times, but these people are clearly not impaired the next day after having smoked the night before.
This subject is going to dog us for some time to come. Marijuana and alcohol are different substances that affect people in different ways, physiologically and psychologically.
If people are concerned about impairment then we should go about determining what that means. The state Supreme Court has given us a nudge in the right direction by establishing that the presence of THC in and of itself does not equal impairment. However, setting a per se level that determines impairment, as the court suggested, isn’t the answer.
Larry Gabriel is a writer, musician and former editor of Metro Times. Send comments to [email protected]