Can I Legally Use Marijuana in Canada then Drive Home to Michigan?

No. Using Marijuana lawfully in Canada puts you at risk of an intoxicated driving charge in Michigan. This is true even though Canada recently passed new federal laws effectively making it legal to possess and use marijuana.  Nevertheless, this new Canadian law may have an impact on how intoxicated driving laws are enforced here in Michigan. To understand why it’s helpful to briefly summarize Michigan’s drugged driving laws.

Until marijuana is also legalized for recreational use, Michigan’s intoxicated driving laws distinguish between the lawful and the unlawful use of marijuana.  For people who can lawfully use medical marijuana, the police and prosecutor must show that the marijuana lawfully consumed substantially lessened the ability to operate the motor vehicle.  In these circumstances, the police and prosecutor will rely on the driving observed and the roadside behavior of the motorist, including the performance on any field sobriety tasks, administered.  Sometimes a blood test result showing a high level of THC in the blood will also be used to bolster their evidence of intoxication.  If the jury believes that all of this evidence shows that the driver was intoxicated, then a conviction for OWI or Operating While Intoxicated will follow.

This level and type of proof are much different for the unlawful use of marijuana where the prosecutor need only show that at the time of driving the accused had any amount of THC in their blood.  This is a zero-tolerance crime, meaning that the prosecutor is relieved of any burden to show intoxication.  Simply having the THC in the bloodstream at the time of operation is sufficient.

Therefore, unless the law in Michigan is changed, you can be found guilty for a zero-tolerance intoxicated driving charge in Michigan even though you lawfully consumed the marijuana in Canada.  Because this result seems unfair, the law could be changed in Michigan so that cases of lawful Canadian consumption are treated differently.  This change might include forcing the prosecutor to show actual intoxication where lawful marijuana consumption across the border can be demonstrated.  At this juncture, such change seems unlikely.

The closest legal scenario involving alcohol would be Michigan’s under 21 BAC law.  Under this law if you are under 21 years of age, then it is unlawful to have any amount of alcohol in your system while driving.  This means if you are 19 and drink lawfully in Canada, you are nevertheless in violation of Michigan’s drunk driving laws as soon as you cross the border in Michigan.

Another similar law is Michigan’s Minor in Possession law.  Under this law, it is unlawful for anyone under 21 to consume alcohol, and violations of this law are subject to the punishments set forth in Michigan Compiled Laws sec.  436.1703.  Subsection 17 of this law indicates that it is an affirmative defense to assert that the alcohol was consumed legally in another venue, and this includes Canada.

Putting this all together then, Michigan could change its intoxicated driving laws so that an affirmative defense such as that set forth in Michigan’s minor in possession statute is added.  Until that happens, however, lawful consumption of marijuana in Canada is not a defense to a drugged driving charge.