Troopers: Washington drivers impaired by 2 or more substances make up most DUI arrests

Drivers under the influence of two or more substances, or polydrugs, are now the most common impaired drivers on our roads, according to Washington State Patrol (WSP)

Trooper Joe Armstrong with WSP said he's seen more DUIs involving drugs recently.

"I arrested 35 DUIs on day shift last year so I get two to three a month. At least one every three weeks out of the month," said Armstrong.

Of the 35 DUI arrests, he said 20 to 25 of them involved drugs. Since the legalization of marijuana in 2012, WSP said marijuana-impaired driving increased 25% and fatal crashes involving THC doubled in the last five years.

"Unfortunately, a lot of people have died on our roadways," said Armstrong.

Cannabis and alcohol are the most common combination found in deadly crashes. AAA found people who use both are the most dangerous drivers on the road.

"The combination of these two substances causes them to speed more, to drive recklessly, go through red lights, more than just using alcohol or marijuana," said Kelly Just, the traffic safety program manager at AAA. 

RELATED: Since pot legalization, driving under influence has steadily risen, state says

WSP deploys its mobile impaired driving unit during special events and holidays. Onboard phlebotomists and drug recognition experts can test you for drugs in the field.

"We have to adjust our tactics to make it quicker and easier for everyone involved and make sure we are keeping up with the times and better serving our community," said Armstrong.

Bottom line: Don't drive impaired.

"The absolute advice is don't drive. If you're going to take part in alcohol or marijuana, that's fine, it's legal if you're above age. Just don't mix it with driving. Don't get behind the wheel," said Sgt. Darren Wright with WSP.

Other impairing substances include some prescription drugs and over-the-counter medication.

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