KUSA - Colorado State trooper Josh Lewis wants to make it clear that he's not out to bust people who partake responsibly in Colorado's newly legal supply of pot.
"It doesn't matter how I feel about it, the law is what it is," Lewis said.
Just like for alcohol, the law for pot is the same: you can't drive impaired.
DUI cases for drugs generally begin with a traffic stop.
"Every reason under the sun," Lewis said. "Too fast, too slow, impeding traffic, not signaling, following too closely, driving on the shoulder, driving on the opposite lane of traffic."
If during a traffic stop, the officer thinks the driver might be stoned, they'll try to figure out if that's the case.
They'll generally ask the driver to take a standard roadside sobriety test.
The tests are meant to look for basic signs.
"Can somebody essentially do two things at once," said Lewis. "Can they count out loud and walk a line? We know in driving you're going to be required to do more than one thing at any given time."
In Colorado, drivers can refuse the roadside test with no penalty, but that doesn't take away the officer's ability to make an arrest on suspicion of DUI.
Whether the driver fails the tests or the officer has reason to believe the driver is stoned for other reasons, an arrest would be made.
At that point, for alcohol, the driver would probably take a breath test.
"For marijuana there is no breath test. It's a blood test or a refusal," Lewis explains.
The blood test is designed to tell how high a person is at the moment, not whether they have been using pot in the last several days or weeks like urine tests used by some employers.
That's because the blood test measures active THC in the blood stream, while the urine tests measure a metabolite of THC, the form it takes after being broken down by the human body.
Colorado law allows drivers to refuse the blood test, too. However, that comes with harsher penalties than a DUI.
"You're going to lose your license longer by refusing," Lewis said.
Ahead of legal sales, state lawmakers adopted a legal blood limit of 5 ng/ml of blood for THC, a move which allows a jury to make a conviction based on test results alone.
That comes long after the traffic stop.
"Nothing has changed for us. We're looking for the same things we have before. Driving under the influence of anything is still illegal," Lewis said.
Pot is about to be easier to get in Colorado. If you use it an drive, a DUI will be pretty easy to get, too.
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