The Interplay Between Legalized Marijuana and Intoxicated Driving

Now that Michigan’s voters have approved the legal use of recreational marijuana, how will this impact Michigan’s laws against intoxicated driving?  The answer is – not very much.

As of the date of this article, it is unlawful in Michigan to drive under the influence of or while impaired by alcohol, drugs, or a combination of alcohol or drugs. This includes marijuana. However, the current state of the law in Michigan is that there are two different standards that apply to marijuana, one for medical marijuana users and one for everyone else.  For a person with a medical marijuana card who is otherwise using medical marijuana legally, the police must prove that the marijuana substantially lessened their ability to operate the motor vehicle.  For everyone else, zero tolerance applies, and simply driving with any amount of marijuana in your system is enough to violate the intoxicated driving laws.

Because marijuana has just become legal to use recreationally in Michigan, it will take some time for the intoxicated driving laws to catch up to this new reality. When they eventually do catch up, two things are likely to happen. First, marijuana will no longer be classified as a zero tolerance “any amount” drug.  This zero-tolerance standard will be replaced by a legal limit for marijuana.  Other states have set arbitrary amounts, such as 5 ng of THC (marijuana’s active ingredient), so the first thing Michigan’s lawmakers will need to decide is this arbitrary legal cut-off.  Next, Michigan’s laws of intoxicated driving, found in the Michigan traffic code’s chapter 257 will need to be amended. Until both things happen, Michigan’s recreational marijuana users will be in a sort of legal limbo while trial courts try to decide the appropriate legal standard for judges and juries to apply in the review of these cases.

Of course, police and prosecutors can always attempt to gain a conviction by showing that your use of marijuana substantially lessened or impaired your ability to operate your car.  However, this is often very difficult, because marijuana typically does not cause drivers to fail field sobriety evaluations or otherwise exhibit poor driving.  Also, some prosecutors and courts may attempt to fall back on the fact that even with state legalization, marijuana remains as a schedule one drug, meaning it is still illegal at the federal level to possess sell or use marijuana.  Consequently, it could be argued that unless and until Michigan’s legislators act, marijuana remains as a zero tolerance any amount drug.