DENVER (WCCO) — If Minnesota’s governor gets his way, state lawmakers will legalize marijuana next year. How could that impact our safety on the roads? WCCO traveled to Colorado to see firsthand the impact of driving while high.

Over a four-minute video, WCCO shows how pot can alter behaviors in an organized driving test in a secured location, supervised by safety driving pros and medical staff. Jennifer Mayerle and photojournalist Lewis Karpel show what happened when three volunteers smoke pot, then get behind the wheel.

What Does Recreational Marijuana Look Like In Colorado?

WCCO enlisted a driving school outside Denver, Colorado, to help put driving-while-high to the test. Master Drive set up cones on a closed course to mimic real driving hazards in order to test speed, reaction time, control, and judgment. WCCO’s Karpel mounted a car with multiple cameras to capture every angle.

Meet the three drivers.

“My name’s Carter. I’m 28, I’m from Denver, Colorado, and I’m a daily cannabis user.”

“My name is Krista. I’m 34-years-old. I consume cannabis frequently, every couple days.”

“I’m Maria. I’m 45, and I’ve been smoking marijuana medically for 3 years but been smoking since high school.”

The on-site nurse tested their blood for THC. Colorado’s Legislature determined 5 nanograms is considered impaired or under the influence.

Maria showed up with twice the legal limit after being asked to not smoke for 24 hours. She regularly uses before driving.

“It is a little difficult, yes, you have to pay attention,” Maria said.

The others weren’t used to driving high. After a couple practice runs it was time for Carter, Krista and Maria to smoke.

The instructors monitored from inside the car and watched from afar.

After smoking once, Carter had a THC level just above what can be prosecuted for DUI in Colorado. Carter’s first run high went pretty smoothly navigating the cones but the instructor, Spencer Pace, noticed he braked harder than when sober. He smoked two more times and drove.

Pace noted Carter drove well but he went a little slower on each drive after using marijuana. Carter says he was concentrating.

“I don’t want to be overconfident. I assume it’s getting worse. But I feel pretty normal throughout it,” Carter said.

Krista smokes the least on her own time and smoked a minimal amount during the driving test. Pace said Krista drove faster after using but her driving didn’t stand out otherwise. After smoking a few more times, she hit a cone and realized she had picked up speed. That continued through her final drive. She admitted she was past her own limit.

“Sorry if I scared you,” Krista said.

“Little bit rougher with the car in sections, rougher with the steering, rougher with braking,” Pace said.

Maria is the 24/7 smoker who says she regularly drives after using marijuana. After her first smoke she was at 3 times Colorado’s current limit for driving. She hit two cones on this drive and wanted to smoke more to get to what she called her normal high. The more marijuana she smoked, the better Maria said she felt behind the wheel. Our instructor said she was more relaxed and talkative but drove a bit rougher. She came close to the edge on a corner. And on her last drive was more than 5 times Colorado’s legal limit.

“I feel really peppy,” Maria said.

By the end of the testing, Maria said she felt too high to drive. Pace said it showed.

“There was a definite degradation in her performance. Just from regular, driving, steering, braking and everything else was much rougher,” Pace said.

“Would you be concerned if someone was driving on the road at the same level you’re at now,” Mayerle asked Maria.

“Yes,” Maria said.

The drivers stayed on course and the instructor didn’t need to grab the wheel or step on his brake. They say they kept an open mind and learned something about their habits.

“Every single one of you there was a noticeable difference when you were smoking from when you weren’t,” Pace said.

“If we’re not maintaining speed well, if we’re not judging speed well, not judging car placement well, those are the things that are indicators of impairment,” Mark Stolberg with MasterDrive said.

“Had I been drinking a big gulp with some of you it would have been all over my lap,” Pace said.

WCCO provided safe transportation for our volunteer drivers.

Colorado recognizes the need for better understanding of how marijuana impairs a driver. There’s no reliable roadside test, yet. And law enforcement is still trying to understand how THC affects different people.

The Colorado State Patrol said any amount of marijuana puts a driver at risk of being impaired. There are challenges, nearly six years after recreational marijuana went into effect in Colorado. Colorado State Patrol said they still don’t have it all figured out. WCCO will share that part of the story Tuesday at 10 p.m.

Jennifer Mayerle

Comments (5)