This year’s Labor Day campaign to catch impaired drivers in Washington has a new target.
The slogan – Drive High, Get a DUI – is intended to call attention to the risk of driving under the influence of marijuana in a state where the drug is legal.
The Washington Traffic Safety Commission is sponsoring extra patrols through Labor Day.
On Wednesday, officers in Spokane Valley told members of the news media that they take the same methodical approach in pot cases as they do for drunken drivers.
Spokane Valley police Chief Rick Van Leuven said his agency has seen an increase in marijuana DUI arrests since pot was legalized by voters in 2012.
That year, his agency made 17 arrests for marijuana-impaired driving. The number increased to 44 arrests last year and 37 arrests so far this year, including a 14-year-old boy, he said.
“It’s pretty safe to assume we will have a lot more people using marijuana,” Van Leuven said about legalization.
Deputy Todd Miller said that while it may be harder to detect marijuana impairment than drunken driving, the telltale signs are there nonetheless.
Being high on marijuana impairs a driver’s ability to judge time and distance, two key skills for safe driving, Miller said. For example, a driver may pull up to a stop short of the line or go over the line. In either case, they could wait an unnecessarily long amount of time to proceed.
Studies show that drivers high on pot may be overly cautious.
In a traffic stop, pot smokers as well as drinkers often will use sprays to cover up odors, another clue of trouble. Marijuana users may have droopy eyelids and dilated pupils, he said. Slow speech is a giveaway.
If impaired driving is suspected, the driver is put through a series of field sobriety tests similar to a DUI stop. A driver high on pot has trouble remembering directions during the tests, said Miller, who is one of 215 trained drug recognition experts in Washington.
Once an arrest is made, the driver could be asked to undergo a 45-minute evaluation that involves a check of pulse, body temperature and blood pressure. More sobriety tests are given. The eyes are checked for abnormal tracking ability, among other elements in the evaluation.
Breath tests are most often used for suspects in drunken driving. For marijuana and other drugs, a blood sample is taken. Drivers can either agree to the blood sample, or a search warrant for blood will be issued by a judge, Miller said.
State law sets an intoxication threshold of 5 nanograms of THC per millileter of blood, but there is little research behind the amount of THC that leads to impairment, said Shelly Baldwin of the traffic safety commission.
But the presence of THC, which is the ingredient of marijuana that gives users a high, will be part of the evidence in a prosecution, officials said.