DENVER - Drug-sniffing police dogs in Colorado may need new training if they can detect marijuana, after a ruling last week by the Colorado Court of Appeals that sets a new precedent for drug cases.

A three-judge panel agreed that if a drug-sniffing dog is trained to alert officers to marijuana and other drugs, cops need more cause to search a vehicle without permission.

The decision came out of a 2015 case in Moffat County, where a drug-sniffing dog named Kilo alerted officers to the presence of an illegal drug in a truck driven by Craig resident Kevin McKnight, The (Grand Junction) Sentinel reported.

But because Kilo could not tell officers whether he smelled pot or other drugs, the search was illegal, judges wrote. The dog was trained to identify to detect cocaine, heroin, Esctasy, methamphetamine and marijuana. Marijuana possession by adults over 21 is legal in Colorado.

“A dog sniff could result in an alert with respect to something for which, under Colorado law, a person has a legitimate expectation of privacy,” judges wrote in the ruling.

“Because a dog sniff of a vehicle could infringe upon a legitimate expectation of privacy solely under state law, that dog sniff should now be considered a ‘search’ … where the occupants are 21 years or older.”

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Courts in other states with legal marijuana for medical or recreational purposes have said that a pot smell alone is insufficient for a warrantless search. Those states include Arizona and California.

The smell of marijuana in a Colorado search is still sufficient if there are other factors that raise an officer’s suspicion.

The Colorado Supreme Court ruled in 2016 that a drug dog’s smell test can “contribute” to a probable cause determination if the suspects are doing something else to raise suspicion.

“The odor of marijuana is still suggestive of criminal activity,” the Supreme Court wrote in that decision.

But in the Moffat County case, judges concluded that the dog’s alert did more than “contribute” to a decision to search the car because the man gave no indication he was impaired or doing anything illegal.

“The police lacked the requisite reasonable suspicion to subject McKnight’s truck to a dog sniff,” judge wrote.

The resulting search turned up a glass pipe commonly used to smoke meth, and McKnight was later convicted of possession of drug paraphernalia and possession of a controlled substance.

The decision reverses McKnight’s conviction.

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