Update: Since this column was published on May 2, it has generated a heated debate among people with more than a casual knowledge of medical marijuana law and how it is applied in our legal system. The prevalent opinion is that my statement that medical marijuana patients cannot legally drive is wrong. 

Attorney John Targowski pointed out that, before June 8, 2010, THC-COOH, the metabolite derived when the human body processes THC, was considered a Schedule 1 drug. However, the Michigan Supreme Court ruled in People v. Feezel that THC-COOH is only a byproduct of how your body processes THC and is not psychoactive, “Thus, anyone can drive with any amount of THC-COOH, patients or not” and not be legally impaired. 

I agree with Targowski and apologize for spreading misinformation. However, a few others say that many prosecutors and judges have a different understanding of the ruling, saying it is irresponsible to say it’s OK to drive with THC-COOH in your system.  

The bottom line is that if you medicate with marijuana daily, then chances are that you do have THC in your system at all times. Whether you feel impaired or not, this makes you legally vulnerable to charges of DWI. 

Again, I apologize for misrepresenting the legal implications of People v. Koon. There are, however, some people who interpret it this way. 

This highlights the need for Michigan law to recognize the science about marijuana and set a fair manner of determining when someone is actually impaired by marijuana use rather than imposing a zero-tolerance standard. 

The amended column below has removed the most extreme implications originally expressed while maintaining the concerns of those who believe that some prosecutors and judges take the position that the Koon ruling applies to all elements of marijuana and their derived metabolites, which linger in the body far longer than THC itself.

On April 17, the Michigan Court of Appeals made a controversial ruling in People v. Koon, a Grand Traverse County case in which a medical marijuana patient was charged with driving while impaired simply because there was marijuana residue present in his system.
The Court of Appeals ruled that the Michigan Medical Marihuana Act does not overrule a zero tolerance law that prohibits drivers from operating a motor vehicle with any amount of marijuana in their system. 

The ruling read: “… in the motor vehicle code, the legislature has provided a definition of what constitutes being under the influence of marijuana: The presence of any amount ... of marijuana.” 

Since marijuana is detectable in the human body for several weeks (whether that's THC or other substances in the plant), that pretty much takes the driving privileges of the state's 130,000 medical marijuana patients away. No driving to work, the doctor's office, the grocery store — nothing.

This ruling is extreme. The motor vehicle code allows for up to .08 blood alcohol content in drivers' systems before they are legally impaired. This ruling reflects an attitude that considers medical marijuana users as criminals.

"The MMMA gives protection for internal possession of marijuana," says Robin Schneider, legislative liaison for the Michigan Association of Compassion Centers. "That's because marijuana stays in your system for 30 days or longer, the impaired time is much shorter than that. That's something I'm hoping law enforcement will take into account and stick with an impairment assessment at a roadside test. I know a lot of people who have HIV and cancer and things like that, and I don't think the voters intended to completely revoke their driving privileges. We created the MMMA so they can have a healthier option of treatment, and I hope law enforcement officers will use discretion when applying this new ruling."

The court's ruling was based strictly on the language in motor vehicle laws and didn't actually present any opinion about what impairment is. Scientific studies in recent decades have shown that marijuana impairment lasts several hours, not days or weeks.

A 1992 U.S. Department of Transportation National Highway Traffic Safety Administration report concluded: "The THC-only drivers had a responsibility rate below that of the drug-free drivers. ... While the difference was not statistically significant, there was no indication that cannabis by itself was a cause of fatal crashes." 

In other words, people who smoke appear to cause no more accidents than drivers who are completely straight. However, when you mix pot with alcohol or other drugs, don't get behind the wheel. Stay home and drive your TV remote.

In addition, the ruling does not take into account the difference between THC and other cannabinoids. THC is the substance in marijuana that causes the high, but other benign cannabinoids might indicate the presence of marijuana in the system but do not indicate impairment. It's an issue that has to be worked out between science and the law. Colorado has considered a THC impairment level at 5 nanograms per milliliter and Washington at 8 nanograms per milliliter. Although neither state has settled on a level, it's a hot topic in both as they face votes on legalization this fall. Ohio and Nevada set the impairment level at 2 nanograms per milliliter, while Pennsylvania sets it at 5 nanograms per milliliter. Those are the only states that have such laws. 

One reason the Court of Appeals ruling concerns medical marijuana activists is that the pending House Bill 4834 in the state Legislature would allow law enforcement officers access to the state medical marijuana registry without a warrant. Some believe this will make patients sitting ducks for police officers who access the registry and find out who is a patient, then stop them while driving. Actually, an officer wouldn't even need to go that far. If a driver produces a registry card at a routine traffic stop, that alone is probable cause for the officer to have the driver's blood tested in order to get a DWI determination.

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