ATLANTA - The number of people being arrested for driving while high on drugs is up 20 percent in Georgia in the past five years.
Channel 2 Action News went to Colorado -- where marijuana use is legal -- to see how officers are cracking down on people driving while high.
Colorado voters approved the use of recreational marijuana a few years ago.
Since then, more people are smoking marijuana and eating edibles, and then getting behind the wheel.
"I've seen somebody driving down the road hitting a bong before," a man who works in the marijuana industry told Channel 2’s Justin Farmer.
Farmer rode along with Cpl. Roger Meyers, a Colorado State Patrol officer who has been trained as a drug recognition expert.
Meyers said when he suspects someone is driving while impaired by marijuana, he starts a conversation with the person.
"How much cannabis have you smoked tonight or how much cannabis have you used tonight?" Meyers said he asks the person.
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We were there as Meyers responded to a call about a pickup truck going 100 mph and weaving through traffic without its headlights on.
Officers initially suspected the driver might be high on marijuana, but after spotting an open container of beer in his truck, they arrested him for driving under the influence of alcohol.
Under Colorado law, the legal limit for marijuana use is five nanograms of THC. That’s five-billionths of a gram.
An estimated 12.4 percent of the deadly crashes in Colorado in 2015 involved a driver who tested positive for cannabis. That's up 8.1 percent since 2013, according to the Colorado Department of Transportation.
"Now as far as crashes, that's a challenge also because everybody that's in a crash impaired is required to test, but some people don't test," said Glenn Davis, highway safety manager with the Colorado Department of Transportation.
Davis said anyone who refuses to take a blood test faces losing his driver's license for one year.
Georgia does not track arrests for driving while high by specific drugs. Numbers we obtained from the Georgia Bureau of Investigation show that between 2010 and 2015, Cobb County police had 609 arrests for driving under the influence of drugs. Atlanta police made 574 arrests and Gwinnett County Police made 541 arrests during that same time period.
Sgt. Dana Pierce, with the Cobb County Police Department, says driving high appears to be a growing trend.
We were with a DUI task force in Henry County as they arrested a teenage driver who was suspected of being under the influence of marijuana.
"Overall appearance of the suspect's eyes, and they also advised me they smelled the odor of marijuana coming from the car," said Jason Jones, with the Henry County Police Department.
Colorado is working to change attitudes about driving high, but many people still think it’s OK.
"But if I go to a friend's house and we get high, and I need to get home, I don't think that I'm being unsafe driving," said the man who works in the marijuana industry.
The Colorado Department of Transportation takes a car that fills with smoke to big events and puts up a billboard to warn people that if you drive high, you'll get a DUI.
"Marijuana is fine. Driving with marijuana is not," Davis said.
Police in Georgia do not have a roadside breath test for drugs, as they do for alcohol.
The Colorado State Patrol is running a pilot program with marijuana DUI devices that test saliva. But there are concerns about those devices.
"Some of those instruments are fairly large and I think that would preclude them being used in a patrol car," Meyers said.
Many of the devices test enzymes that are sensitive to heat and cold.
"If it's below a certain temperature, if it's below freezing, which in Colorado, God forbid, it gets below freezing," Meyers said.
Davis says devices should not replace good old-fashioned law enforcement.
"It's not about a device. Can law enforcement who stops somebody detect impairment and articulate that impairment?" said Davis.
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