In 2023, Minnesota legalized marijuana use. And, since the 1970s Minnesota incrementally reduced criminalization of people with marijuana (cannabis). So, though the “odor of marijuana” is an unchanging fact, the legal status of marijuana, or cannabis, has changed. As a result, we ask: does “odor of marijuana” still give police officers probable cause to suspect criminal activity?
Questions of Fact vs. Law
Courts distinguish between “questions of fact” and “questions of law.” For example, an appellate court reviewing a trial court’s decision will defer to the trial court judge’s decision on questions of fact, more than it will for questions of law. Why?
During a Contested Omnibus Hearing, and during a trial, the trial court judge heard the testimony of witnesses, saw the evidence. But the appellate court generally only has the trial court’s written transcript and record, for review.
So the Minnesota District Court (trial court) Judge generally determines the facts. In the end, however, the Minnesota Court of Appeals, Minnesota Supreme Court, and federal appellate courts, have the last word on what the law is.
Sometimes the difference between an issue of fact vs. law is clear. But other times an issue may seem a mixed issue of fact and law.
Marijuana Use was a Crime, Now Lawful
Setting aside issues of fact for the moment, assuming an “odor of marijuana,” so what? After all, marijuana use is now legal in Minnesota. Alcohol use is legal. Tobacco use is legal. Why would the odor of marijuana be probable cause to suspect a crime? It’s not a crime — not any more. Since the 1970s, Minnesota law changes include:
- Decriminalization of Small Amount, up to 42.5 grams of marijuana flower (petty misdemeanor)
- Medical Cannabis program, via Minnesota Department of Health (legal)
- Hemp, Cannabis with less that 0.3% THC, including hemp flower and CBD products (legal)
- Low-THC Cannabis Edibles and Drinks (legal)
- Adult-Use Cannabis, marijuana (legal)
Living in the past? Are any judges still “fighting the last war?” Yes, inertia has power. And change can be challenging. But the legislature changed the law. Marijuana use is no longer a crime. So, if a person may reasonably suspect that the odor of marijuana means another person used marijuana, what difference could that possibly make now that marijuana use is legal?
The inescapable conclusion must be that odor of marijuana alone, cannot be a reasonable basis for suspecting criminal activity. So, odor alone cannot be a basis for “reasonable articulable suspicion of criminal activity,” much less “probable cause of criminal activity.”
Numerous Minnesota old appellate court decisions have held the contrary, that the odor of marijuana can be a basis of probable cause to suspect criminal activity. Most of those cases involve facts with more than just odor. But all of them predate marijuana legalization in Minnesota.
If before August 1, 2023 in Minnesota, the odor of marijuana was the odor of a crime; that is no longer the case. This shift in the legal environment is now a historical fact. So any Minnesota court decisions prior to August 1, 2023, on odor as probable cause, have in effect been legislatively overruled. For more see my page: Minnesota Marijuana Laws.
Terpenes vs. Cannabinoids
SOURCE OF ODOR: Terpenes are the chemical compounds that give fragrant aromas to plants and flowers.
ODORLESS: Cannabinoids are chemical compounds in cannabis plants (and animals), including D-9-THC & CBD. And cannabinoids are odorless.
So, odor is not associated with THC or other cannabinoids. They are odorless. And as a result, a assuming that the odor of cannabis means adult-use cannabis or THC is present would be incorrect. Of course, since adult-use cannabis is legal and not a crime, even that false assumption should not give rise to suspicion of crime.
Cannabis plants have the same odor
Regardless of legal status of cannabis plant; whether hemp, medical, adult-use; all are the same plant, cannabis. All are from the same botanical category: genus Cannabis. A cannabis plant smells like a cannabis plant, regardless of THC level of that plant.
The artificial, legal categories do not correlate with odor. We cannot distinguish between them using odor. So an odor of marijuana no longer implies presumptively illegal conduct.
The difference between legal hemp, legal cannabis and illegal cannabis is the concentration of THC. So, a police officer cannot differentiate between legal hemp and illegal cannabis by sight or smell but only through sophisticated testing.
What about … ?
What about possession of more than the amount of adult-use cannabis that the law currently allows? Isn’t possession of more than two ounces in public, or two pounds at home, still a crime?
Yes, marijuana Prohibition of possession lingers in Minnesota. But how would odor give rise to reasonable suspicion of crime, where use and possession are both lawful unless over two ounces in public? In other words, what does odor have to do with quantity? Wouldn’t police need more, like a reason to suspect possession of more than two ounces?
What about federal law? Federal law includes a stated policy of non-enforcement of federal marijuana crimes against individuals who are state-law compliant. (No money is to be spent on it.) So unless police are on federal land, they’re not enforcing federal law.
Most Cannabis Categories: Presumptively Lawful
Now in Minnesota, almost all legal categories of cannabis that police may encounter are not crimes:
- Hemp flower
- CBD products
- Low-THC Edibles & Drinks
- Adult-use in Public
- Possession of Adult-Use Cannabis up to Two Ounces in Public
- Medical Cannabis
And the exceptional situations where some cannabis may be unlawful, are comparable to those exceptional situations where alcohol and tobacco are unlawful. Would odor of tobacco mean suspicion of a crime? If not, why would the odor of marijuana?
Exceptions: When Alcohol, Cannabis, Tobacco Not Lawful
But in exceptional situations, alcohol, cannabis, and tobacco might not be lawful:
- Underage, of 21
- Motor vehicle, if “open container” (alcohol and cannabis)
- Quantity, over limit (adult-use cannabis)
In each situation where these substances might be illegal, the fact of the presence of the substance alone would not be enough to suspect crime. A police officer would need reason to suspect the fact of an additional element of a crime, such as age, open container, quantity. So, odor alone cannot be enough to suspect a crime.
Odor alone is never PC – unless the substance is presumptively illegal, like marijuana was. But after August 1, 2023 in Minnesota, no longer. Marijuana is presumptively legal, like alcohol and tobacco.
“Claims that cannot be tested, assertions immune to disproof are veridically worthless, whatever value they may have in inspiring us or in exciting our sense of wonder.”
Carl Sagan
Fact of Marijuana Odor: Problems of Proof
Now let’s shift from the legal issue, to problems of proof. How do you prove a fact? Lawyers, and judges have legal problems they call: “problems of proof.” You may “know” something to be true, but can you produce admissible evidence of that fact in a court proceeding?
How can a prosecutor prove that a police officer smelled the odor of marijuana? They have that police officer testify.
“The present findings throw into question, in two specific instances, the validity of observations made by law enforcement officers using the sense of smell to discern the presence of marijuana. [T]hey … suggest acceptance of testimony based upon reported detection of odors for probable cause is questionable and that empirical data to support or refute such testimony in specific cases is sorely needed.”
Marijuana Odor Perception: Studies Modeled From Probable Cause Cases, Richard L. Doty, et al, Law & Human Behavior, Vol. 28, No. 2, April 2004.
Potential for Police Abuse: Odor of Marijuana
Query: If a police officer claims the odor of marijuana as justification to search a car, and finds no evidence of crime, releases the driver; will a judge ever hear about it? But if a a police officer claims the odor of marijuana to justify a search, then does find evidence of crime, does that corroborate the claim of odor?
If so, then can police claim odor of marijuana without fear of meaningful review or supervision of that claim by a court?
A landmark Minnesota Supreme Court case addresses a similar problem, that of recording statements, in State v. Scales:
“an accurate record makes it possible for a defendant to challenge misleading or false testimony and, at the same time, protects the state against meritless claims. Recognizing that the trial and appellant courts consistently credit the recollections of police officers regarding the events that take place in an unrecorded interview, the court held that recording “is now a reasonable and necessary safeguard, essential to the adequate protection of the accused’s right to counsel, his right against self incrimination and, ultimately, his right to a fair trial.” Stephan v. State, 711 P.2d 1156, 1159-60 (Alaska 1985). A recording requirement also discourages unfair and psychologically coercive police tactics and thus results in more professional law enforcement.”
State v. Scales, 518 NW 2d 587 (Minn. Supreme Court 1994)
Trend: Odor of Marijuana Not Probable Cause
With legalization, the trend no longer allows police to use odor of marijuana as reason to suspect crime.
Legislation: Some states now have statutes saying odor of marijuana alone is not a reason to suspect a crime, e.g., Virginia.
Courts: And some state courts ruled odor of marijuana alone is not probable cause to suspect crime, e.g., Pennsylvania Supreme Court.
Unreasonable Searches & Seizures Prohibited
The Fourth Amendment provides:
“The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”
U.S. Constitution. Amend. IV
And the Minnesota Constitution can provide greater protections that the federal Constitution:
“The right of the people to be secure in their persons, houses, papers, and effects against unreasonable searches and seizures shall not be violated; and no warrant shall issue but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched and the person or things to be seized.”
Minnesota Constitution, Art. I, Sec. 10
Minnesota Supreme Court: Odor of Marijuana Not Probable Cause
The Minnesota Supreme Court held on September 13, 2023, in State v. Torgerson, A22-0425, that the odor of marijuana alone did not create a fair probability that an automobile search would lead to the discovery contraband or evidence of a crime, and therefore the evidence obtained in the search must be suppressed.
The court notes that the odor of alcohol alone does not give police probable cause to search a car for an open container of alcohol. Therefore, the odor of marijuana alone does not give police probable cause to search a car for an open container of cannabis in a motor vehicle.
Legislature: Odor of Marijuana Not Basis for Search
A new Minnesota statute effective 2024 codifies the holding in Torgerson.
“A peace officer’s perception of the odor of cannabis shall not serve as the sole basis to search a motor vehicle, or to search the driver, passengers, or any of the contents of a motor vehicle.”
Minn. Stat. §626.223 ODOR OF CANNABIS; SEARCH PROHIBITED
So, a police may not lawfully search a vehicle based only upon odor of marijuana. If they do, they have not only violated the statutory law, but also constitutional law.
Minnesota Courts: Odor of Marijuana Not Justification for Expanded Stop
In State v. Babineau, A23-1515 (Minn. App. 5/19/25), the Minnesota Court of Appeals held that under the Minnesota Constitution, the odor of marijuana coming from a vehicle does not, on its own, provide reasonable, articulable suspicion of criminal activity sufficient to expand the scope of an equipment-violation vehicle stop.
The scope of an investigatory vehicle stop “must be limited to the justification for the stop,” pursuant to State v. Burbach, 706 N.W.2d 484, 488 (Minn. 2005). The state bears the burden to demonstrate that an investigatory stop was “sufficiently limited” in scope and duration. State v. Askerooth, 681 N.W.2d 365 (Minn. 2004).
Question? Call Attorney Thomas Gallagher, 612 333-1500
Attorney Thomas C. Gallagher is a Minnesota criminal defense attorney who regularly represents clients accused of cannabis crimes. He also serves on the Board of Minnesota NORML, working to fully legalize marijuana.
He frequently litigates and discusses the changing issue of whether odor of marijuana is still probable cause to suspect a crime.
More: Odor of Marijuana
How to Avoid a Marijuana Arrest in a Car: Nine Tips
Marijuana in a Motor Vehicle
Illegal Search
Large Marijuana Case on I-94; Gallagher Wins Illegal Search