The seven justices on the Kansas Supreme Court ruled today that marijuana odor constitutes probable cause for police to search a private residence without a warrant, the AP is reporting. The 4-3 ruling says that an officer’s detection of a marijuana smell is enough cause to conduct a warrantless search. The case wound up in state supreme court after a lower court failed to demonstrate the lawfulness of a police search of the home of Lawrence Hubbard. During a sweep, police found roughly an ounce of cannabis in a closed container in a closet of Hubbard’s home.

Supreme Court Says If Police Smell Weed, They Can Search a Home Without a Warrant

Kansas police arrested Lawrence Hubbard in November 2013 after entering his apartment and discovering about 25 grams of cannabis locked inside a safe. Police also say they found a small amount of weed in a half-smoked cigarillo. In court, Hubbard’s defense attorney argued to suppress the evidence of drugs, on the grounds that the initial warrantless search violated Hubbard’s constitutional rights.

Furthermore, Hubbard’s defense challenged the testimony of the arresting officers as expert witnesses. Defense attorney Jim Rumsey argued “no reasonable person” would be able to detect an ounce of cannabis in a container, inside a safe, inside a closet 30 feet away from a closed apartment door.

But in the majority opinion, Justice Dan Biles upheld Hubbard’s misdemeanor conviction on drug charges. Biles wrote that officers don’t have to be cannabis experts to know what weed smells like, and that smelling weed is not a complex sensory task. “We are not dealing with sommeliers trying to identify a white wine as a Loire Valley Chenin Blanc,” Justice Biles wrote. The dissenting opinion, authored by Justice Carol Beier, said the courts should reverse Hubbard’s convictions and vacate his probation sentence.

Douglas County assistant district attorney Kate Butler, who argued the state’s case in Hubbard’s trial, described the arresting officers as “very familiar with the smell of marijuana”. During their testimony, the officers described the smell as “overwhelming, potent and very strong.”

Court Uses “Marijuana Smell” To Justify Warrantless Searches

Kansas already permits police officers to search vehicles without a warrant if they smell marijuana. Today’s Supreme Court ruling essentially extends that authority to the search of private residences. Critics of the ruling say it raises a number of constitutional and civil rights issues.

In the first place, a police officer’s claim to have detected a marijuana odor isn’t falsifiable. There’s no standard of evidence or burden of proof that can show conclusively an officer did not smell weed. Conversely, there’s no way for an officer to prove that they actually smelled weed. Thus, simply by saying they smell cannabis, an officer has the authority to conduct a warrantless search of someone’s home or vehicle.

Additionally, marijuana odors are notoriously mobile. Smells can creep under doors and down hallways, move through open windows and from passing vehicles and pedestrians. In other words, it can be very difficult to pinpoint the origin of a marijuana odor. Yet the tell-tale smell of marijuana has always been a potent tool for law enforcement. A whole industry exists to provide products and techniques to hide the smell of marijuana for consumers requiring discretion.

Then, there’s the question of human olfactory capability. How much weed triggers a sense of its smell? How near or far does a person have to be to smell weed or not smell it? What length of time does the smell linger? These were all questions Rumsey posed to the court. But they did not sway the majority opinion of the justices. Some states have passed laws eliminating marijuana odor as probable cause, like Arizona and Massachusetts.