Marijuana: Amendment 64 causes problems for drug dogs with a nose for pot

How useful is a drug dog trained to go after something that is now legal in two states? Since it's no longer a crime to carry up to an ounce of marijuana in Colorado, the mere fact that a drug dog has detected marijuana isn't reason enough to search someone.

And because a dog is trained to detect not just marijuana but other drugs, such as meth, it might be tough to prove in court that a dog alerted the authorities to an illegal drug rather than the legal one.

"Basically, there is no way to un-train the dogs to not do marijuana," says John Schulz, spokesman for the Larimer County Sheriff's office. "So it really hamstrings the use of the dogs. What it boils down to is, we can't use the dog sniff anymore as a reason for probable cause."

That doesn't mean Larimer County's dogs -- Oso, Grendel, Ryker and Arco -- are getting lazy, though. Schulz says the dogs are used when law enforcement has the legal right to search somewhere based on other factors. "If we find marijuana [in that instance], we can ignore it," he notes, "but they may find other things as well."

Loveland police are thinking ahead, and training their latest pup -- a Dutch shepherd named Shadow -- to ignore the scent of cannabis completely; she'll still be schooled to sniff out still-illicit drugs, as well as how to drag a fleeing suspect to the ground. The dog is the third for the department, but the first to be trained in this way. When the department gets a fourth dog, it will be trained like Shadow.

Schulz says that when Larimer County adds more K-9 unit dogs, they will be trained to ignore marijuana, too. In the meantime, he notes, county authorities can always call on Shadow if they need an extra hand -- or, more specifically, a nose.

Interestingly, Seattle police have come to a different conclusion regarding their canines. After Washington voters approved Initiative 502 in November, legalizing small amounts of marijuana for personal use, the Seattle Police Department started retraining its dogs. And after two months of training, according to KOMO News in Seattle, a "general tracking dog" now ignores marijuana.

More from our Marijuana archive: "4/20 at CU-Boulder: Rob Corry explains why he won't challenge campus closure" and "Marijuana retailers may not have to grow their own -- and that's great, attorney says."