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Western states have led the way in the legalization of marijuana. The move began with medical marijuana, then last November voters in Colorado and Washington state legalized recreational pot. And that's meant quite an adjustment for the police. NPR's Martin Kaste spent some time with the Washington State Patrol to see how they're handling the new reality.
MARTIN KASTE, BYLINE: I'm driving through Seattle on Interstate 5. It runs from Canada clear down to Mexico and the cops sometimes call it the pot highway because of all the marijuana that they've intercepted on this route. But things are a little different now. To test just how different, I'm carrying.
It's a legal amount, under state law at least. It's less than an ounce. Actually, it's just a little bud, but it's sitting right here in my cup holder in plain sight. And I have to say it feels kind of weird to have it there, especially because I'm on my way to see some state troopers, troopers with drug-sniffing dogs.
STEVE GARDNER: This is what we would classify as monthly maintenance training.
KASTE: Steve Gardner trains these dogs to detect cocaine, crack, meth and heroin, but not marijuana, not anymore. State lawyers decided that things would be simpler this way since a dog's nose can't tell the difference between legal and illegal quantities of pot.
UNIDENTIFIED WOMAN: Oh, you found it! Oh, you found it!
KASTE: This is Piper, one of the first dogs trained since legalization. She's just found another drug, not pot, and she's getting her reward.
During her search, she never once took any notice of me or that bud of marijuana now tucked into my coat pocket. There's just one problem. Gardner says the older dogs can't unlearn the scent.
GARDNER: It's a perishable skill. Over time it becomes less sharp for them, but once you've trained them to detect it, you're not going to get them away from it.
KASTE: But from now on, the new dogs will never be trained on marijuana, and Dave Rodriguez thinks that's a shame.
DAVE RODRIGUEZ: That was an important tool, using drug dogs to help you establish probable cause.
KASTE: Rodriguez is a federal official based in Seattle. He works for the office of the drug czar. He says big drug busts may be harder to come by now in the Northwest because local cops are rethinking what to do when they encounter marijuana.
RODRIGUEZ: Everybody's very cautious because they don't want to get sued. They don't want to set bad case law, you know. Can you continue to trust your judgment?
KASTE: It's pretty clear Rodriguez doesn't like legalization, but he echoes the wait-and-see policy recently laid out by the Justice Department. The real test of that comes next year when growers start producing marijuana under state license. The feds say that pot had better not show up in the rest of the county.
(SOUNDBITE OF POLICE RADIO)
KASTE: The other big policing issue when it comes to marijuana is stoned drivers.
RAY SEABURG: My name is Trooper Ray Seaburg. I am a trooper with the Wash. State Patrol.
KASTE: Seaburg is part of a dedicated DUI unit and he's out roaming Seattle's nightlife areas. He says legalization has changed the rules of engagement with drivers, especially when he encounters evidence of pot use.
SEABURG: Initially, when I'd smell marijuana when I first came out, that was like, oh my gosh, OK, there's a misdemeanor crime occurring right in front of me.
KASTE: That used to be when the handcuffs came out. Nowadays, the smell of pot leads first to some careful questions.
SEABURG: How long ago did you smoke? Did you smoke? Do you have any in your possession? How often do you smoke?
KASTE: If the driver seems impaired, it's off to the hospital for a blood sample. The initiative legalizing pot set a blood level limit for THC, that's the active ingredient in marijuana. If you hit 5 nanograms per milliliter, you're in trouble. Even so, police say legalization has actually made drivers more willing to volunteer information.
SEABURG: With the marijuana, it seems that people are, you know, oh, I just smoked a little bit ago. Or I just smoked. So...
KASTE: And they'll just say that to you.
KASTE: And there's now evidence that legalization has led to more drivers with pot in their systems. NPR has obtained preliminary statistics from the state toxicology laboratory, and they show a jump in the percentage of blood tests for suspected DUIs that contain detectable amounts of active THC. Through last year, that percentage hovered around 20 percent. This year, it's running closer to 27 percent. That's a seven-point increase since legalization.
Seaburg says he's especially worried now about people who are trying it for the first time.
SEABURG: You're talking about a stick of dynamite there essentially, because that person doesn't know how they're going to react to the marijuana they smoke, because they've never done it before, because it was illegal before.
KASTE: Defense lawyers report that they're seeing more of these cases; they sometimes call them green DUIs. And actually, that's kind of what the sponsors of legalization promised last year: To make marijuana more like alcohol, a taxed, regulated drug that can get you a DUI.
Lawyer Jesse Corkern sees that analogy to booze. But he thinks most people in Washington state aren't quite there yet.
JESSE CORKERN: You go to the store and you pick up a six pack, you throw that in with your groceries. You don't think anything of it, right? I mean it's perfectly legal to have that. We don't have that same approach to cannabis yet as a populace. I mean, yes, it's legal, but it's going to take a while for people to get to that comfort zone with, you know, with cannabis.
KASTE: And that includes the police. Corkern says yes, it's undoubtedly legal now to, say, carry marijuana in your car's cup holder. But is it really a good idea? He'd advise a little more discretion.
Martin Kaste, NPR News, Seattle.