You're relaxing in your car when a police officer knocks on your window. When you roll it down, a pungent waft of marijuana smoke hits the officer in the face. He then orders you out of your car, searches your vehicle, and finds marijuana. Wait, he didn't have a warrant to search! He tells you he doesn't need it because he recognizes the smell of marijuana.
Is it legal to do a warrantless search based on the smell of marijuana?
Unreasonable Search and Seizure
The Fourth Amendment prohibits unreasonable searches and seizures. In most cases, police must have a warrant to search you and your personal belongings. To get a warrant, police must have probable cause to believe that evidence of a crime may be found.
There are certain circumstances where a search may be done without a warrant.
Plain View Exception
The plain view exception allows officers to seize incriminating evidence without a search warrant when the evidence is in plain view.
If a gun is on top of a table and easily observable, it is in plain view. If the officer had to lift up a magazine to see the gun underneath, then it is not in plain view.
Plain Smell Exception?
The plain smell theory parallels the plain view exception. Proponents claim that smell should be enough to constitute probable cause for a warrantless search. But not all courts agree on the plain smell exception.
In United States v. Miller, the Ninth Circuit held that plain smell, when paired with a plain view observation, is enough to justify a warrantless search. In this case, the officer smelled an odor of phylacetic acid, used to manufacture methamphetamine, emanating from the defendant's car. When he looked in through the window, he also saw a gun in plain view. The smell of phylacetic acid along with the sight of the gun gave the officer enough probable cause to search the car without a warrant.
Also, courts have long recognized that exigent circumstances may justify the warrantless search of a car if there is probable cause. In People v. Kazmierczak, the Supreme Court of Michigan ruled that smell alone can justify a warrantless search of a car.
However, in People v. Marshall, the court held that smell creates probable cause to get a search warrant but does not justify a warrantless search. The court wrote, "Even a most acute sense of smell might mislead officers into fruitless invasions of privacy where no contraband is found."
With the courts divided on the issue of plain smell, whether or not a warrantless search based on the smell of marijuana is legal depends on the case law in your state. If an officer has searched your car because of the smell of marijuana, an experienced local criminal defense attorney may be able to help you determine the legality of that search.