Law enforcement officers in Washington are no longer just asking drivers if they’ve been drinking when they’re pulled over, as legalized marijuana in the state adds the question, “Have you smoked anything today?”

The Washington State Patrol on Wednesday brought in local drug recognition experts to explain the process for determining driver impairment during traffic stops for substances other than alcohol, which takes about 45 minutes and typically happens after an arrest has been made.

Bellevue Police Lt. Marcia Harnden said the effects of alcohol and marijuana are not only different, but the effects of marijuana can also differentiate among users based on factors like smoking-versus-ingesting and the potency of marijuana and its products.

While 5 nanograms per milligram is the limit for marijuana impairment through blood testing, it doesn’t mean a driver under the limit isn’t still impaired. It is also difficult to say how soon following consumption of marijuana a person should get behind the wheel.

“Our recommendation is better to be safe than sorry,” Harnden said, adding marijuana legalization occurred in Washington quickly, leaving little time for research to be done to assist police with enforcement. “It’s just a matter of learning more and more.”

There are 215 drug recognition experts in the state. All DREs undergo rigorous training to be able to detect drug impairment, and Harnden said many impaired drivers tend to be under the influence of more than one drug.

Washington State University is currently developing a roadside breath test for marijuana, which could be a great asset to police.

Drivers still have the option of refusing to take the test.