Driving Under the Influence

Driving under the influence of alcohol and/or drugs is a leading factor in Washington traffic deaths. Troopers are responsible for nearly 50% of the DUI arrests in the state, however, even one driver under the influence is too much.

If you believe someone is driving under the influence, please immediately call 9-1-1.

What’s Considered a DUI?

Driving under the influence (DUI) refers to operating a vehicle while affected by alcohol, drugs, or both. This applies to both legal and illegal drugs, including prescription medication and over-the-counter drugs.


How is DUI determined?

A driver may be charged with DUI if:

The results of a breath or blood test show the amount of alcohol in the driver’s blood to be:

  • .08 or higher for adults (21 and over).
  • .04 or higher for commercial vehicle drivers.
  • .02 or higher for minors (under 21).


  • He or she is found to be driving a vehicle under the influence or affected by alcohol, any drug, or a combination of alcohol and drugs, regardless of the concentration of alcohol in their breath or blood.

Our Role

The Washington State Patrol considers removing intoxicated drivers off of our roadways a top priority. As part of the Target Zero, which aims to reduce the number of highway deaths to zero by the year 2030, troopers are on the lookout for impaired drivers every day. However, certain areas of the state where history shows the most DUI fatalities or serious collisions are staffed with Target Zero Teams. To learn more about Target Zero, see our Driver’s page.