THURSTON COUNTY, Wash. - In a test that’s never before been done in Washington, KIRO 7 Eyewitness News had volunteers smoke marijuana and then put them behind the wheel to show what stoned driving looks like and the danger on the road.
To find out how much marijuana is too much to get behind to wheel, KIRO set up a driving course.
KIRO also recruited drug recognition expert Casey Lee and had marijuana for the volunteers.
“This strain is actually called blueberry train wreck,” said Lee.
As a consultant prepared the marijuana smoking lab, three volunteers each took a practice run on a course set up by the Thurston County Sheriff's Office that was designed to test their basic driving skills.
In the car with them was Cascade Driving School instructor Mike Jackson, who had a brake on his side of the vehicle for safety.
“I can either grab the wheel or touch the brake and bring them to a safe stop,” said Jackson.
The first volunteer, Addy Norton, is a 27-year-old medical marijuana patient and heavy daily marijuana user who smoked pot before arriving at the test site.
A blood test before the experiment began showed Norton came to the track at already three times the legal limit of 5 nanograms for driving under the influence of marijuana. Norton tested at nearly 16 nanograms.
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While learning the course, Norton turned too sharply at a stop sign and clipped one of KIRO’s cameras, but the instructor said her driving was actually fine.
KIRO’s second volunteer was 34-year-old Dylan Evans, who uses pot on weekends.
An initial test showed no marijuana in his system.
The third volunteer was 56-year-old Jeff Underberg, who uses only occasionally. He also started out with no detectible marijuana in his system.
Next, the volunteers started smoking marijuana. They were each given 3 tenths of a gram of pot to smoke, and from the light to the heavy user, KIRO asked them how they felt.
“I’m really buzzed, yeah,” said Underberg.
“Relaxed and buzzed,” said Evans.
“I can’t feel it yet,” said Norton.
While Norton was back behind the wheel for another lap, she drove a bit slower than she should have, and at one point, struck a traffic cone.
“I hit a cone. I see it in the rearview mirror, ah,” said Norton.
A blood test would later show that Norton was driving at seven times the legal limit for pot with 36.7 nanograms of marijuana in her system, but she was still driving OK.
“I wouldn’t pull her off the road yet. No, not at this point,” said driving instructor Jackson.
After 3 tenths of a gram of pot, Evans was doing fine behind the wheel, even though KIRO’s lab test would later reveal that Evans was driving at five times the legal limit, with 26 nanograms of pot in his system.
When Underberg was on the track, he was being cautious and driving slower than he should, which could catch a police officer’s eye on the road.
Underberg’s blood tests showed the he was at four times the legal limit, with 21.7 nanograms in his system, but again, while his driving was slow, it was still acceptable.
“He did real well,” said Jackson.
KIRO had the volunteers smoke and drive two more times until they had all smoked 9 tenths of a gram of pot -- and were feeling it.
“I’m starting to get it, oh yeah. I can feel it in my eyes. I can feel it in my body and my head,” said Norton.
And it started to show more on the road.
With a drug recognition expert from the sheriff's office watching, Evans started having trouble remembering how to drive the course.
“What, is this cone in the middle?” said Evans.
Confused, Evans turned early and left the course.
Then while going through a 20 mph corner, the instructor had to grab the wheel to stop Evans from swinging wide and hitting KIRO’s photographer.
“I had to grab the wheel, basically, to stop him from running (the photographer) over,” said Jackson.
“If I was to be watching him on a road, I would have stopped him,” said Officer Dave Claridge with the Sheriff’s Office.
Underberg’s driving also got worse with the more pot he smoked.
He backed over a cone, and after 9 tenths of a gram of pot, he drove so slowly the officer said he should not be on the road.
After 9 tenths of a gram Norton was becoming much more aggressive and was excited about being high behind the wheel.
“One time in your life you get to do this, you should do it. You should do it (laughs). Yeah. That’s awesome,” said Norton.
Yet Norton made no major mistakes. KIRO 7 asked the officer if he would pull her over.
“(She’s) borderline,” said Claridge.
KIRO decided to allow Norton to smoke one last time, bringing her total smoked to 1.4 grams.
When she was back in the car, Norton knew she was having trouble.
“(I’m) way more stoned. Way more stoned. Definitely shouldn’t be driving,” said Norton, who swung wide on a 20 mph curve as she drove with no restraint.
Less than 30 seconds into the drive, she started backing up and didn't stop until she wiped out a cone.
“Which would have been indicative of backing into a pole or a citizen on the sidewalk,” said Claridge.
The officer, driving instructor and Norton agreed she would not be safe if she was on a public road.
“She would be a danger,” said Jackson.
To confirm the volunteers were driving impaired, KIRO treated them like anyone else who was pulled over for suspected drug use.
The county's drug recognition expert put them through a 12 step evaluation, checking things like their balance, heart rate and blood pressure.
They all had issues including Underberg, who couldn't find his nose with his finger tip.
“I would say all three would have been arrested for driving under the influence of marijuana,” said Claridge.