Can police really smell cannabis in your car?

It’s difficult to imagine that 52 pounds of cannabis wouldn’t smell

A new study, inspired by the real arrest and confiscation of a massive amount of tightly sealed cannabis, suggests it’s possible. Though the study tested two ounces instead of over fifty pounds, the results could change the way defendants fight police searches based on the “in plain smell” doctrine.

In the study, which will be published in the March 2020 issue of Science & Justice, two researchers found that people can’t smell marijuana packed in double vacuum-sealed bags. The study examined the ability of the human nose to identify marijuana when it was packaged in different ways. The scent was still obvious in casual packaging like Ziploc sandwich bags, but heavier plastics and seals stopped the odor from escaping, according to the study.

“There’s a lot of anecdotal evidence that at least some officers say they smell it when they don’t,” said Alex Kreit, an expert in marijuana law and visiting researcher at the Ohio State University Drug Enforcement and Policy Center.

A common situation that shows the flaws of the doctrine is a when a smell-based search turns up cocaine, but not marijuana. An officer may suspect drug possession and say they smell marijuana in order to search a car, when in fact there was no evidence of any marijuana that they could have smelled.

“That type of fact pattern suggests that they just wanted to search the car,” said Kreit.

The US Supreme Court ​has ruled that as long as an officer pulls someone over for a legitimate ​reason, the officer’s motivation is irrelevant. A cop could see a car, decide it’s suspicious, and follow it around until the driver does something illegal, Kreit explained. And every driver eventually does something, even if it’s driving one mile above the speed limit.

Once the car is pulled over, the plain smell doctrine can come into play as probable cause. But the one-two punch of broad possibilities to pull someone over and reliance on the human nose leaves the door open to profiling.

Mike’s defense lawyers took a novel approach in challenging the search: science. They hired Dr. Avery Gilbert, a scientist who specializes in odors, and Dr. Joseph DiVerdi, a chemistry professor at Colorado State University, to examine the evidence at a state police station.

With the cooperation of the police, Gilbert and DiVerdi collected extensive air samples. First they took samples of the air inside the evidence bags that held the vacuum packs, said Gilbert. Then Gosnell filled the confiscated duffle bags with the marijuana and DiVerdi took air samples from inside the duffels.

Back in their lab, they tested for concentrations of six terpenes, the compounds that give marijuana its odor. They ran the samples through a gas chromatography machine to separate and analyze the compounds.

The science backed up their supposition. The terpene levels were all too low to be detectable by people, said Gilbert. Their report is confidential because the case did not go to trial. Instead, the defense attorneys and the prosecutor reached a plea agreement.

Read the full article at Leafly