Washington DUI investigations changed in 2026 with the introduction of voluntary roadside oral-fluid testing.
Under RCW 46.61.5062, Washington law enforcement agencies may use approved oral-fluid testing devices during roadside DUI investigations. These devices analyze a saliva sample and may give officers additional information while they investigate suspected impaired driving.
For drivers, however, the roadside saliva test comes with important protections.
Do You Have to Take a Roadside Saliva Test?
No. Washington law requires the officer to tell you that the oral-fluid test is voluntary.
Before administering the test, the officer must also explain that:
- Taking the saliva test does not satisfy Washington’s implied consent requirements;
- The result may not be used against you in a court of law; and
- The saliva test does not replace an evidentiary breath or blood test.
This is an important distinction because not every test requested during a DUI investigation carries the same legal rules or consequences.
A voluntary roadside saliva test should not be confused with evidentiary breath or blood testing that may be requested after a DUI arrest.
Refusing the Saliva Test Does Not End the DUI Investigation
Because the roadside oral-fluid test is voluntary, a driver may decline it. However, declining the test does not require an officer to end the investigation.
Police may continue relying on other evidence, including driving behavior, statements, physical observations, field sobriety testing, preliminary breath testing, or other circumstances surrounding the traffic stop.
If probable cause develops, an officer may still make a DUI arrest and seek additional evidentiary testing as permitted under Washington law.
Saliva Samples Have Special Privacy Protections
Washington’s new law also limits what law enforcement may do with the biological sample.
Agencies using roadside oral-fluid testing must establish procedures for destroying the saliva sample after obtaining the test result. The statute provides for strict liability if an agency fails to destroy the biological sample within 24 hours or unlawfully enters DNA information into a database.
These safeguards are separate from the legal rules governing whether other DUI evidence may ultimately be used in a criminal case.
Learn More About Washington’s 2026 Saliva-Test Law
Roadside saliva testing is only one part of a Washington DUI investigation. Whether the stop, arrest, testing procedures, or other evidence can be challenged depends on the circumstances of the individual case.
For a detailed explanation of the new law, including what officers must tell you, how the test differs from breath and blood testing, and what happens to your biological sample, read our 2026 Washington DUI Saliva Test Guide.
If you have been arrested or investigated for DUI in Washington, Blanford Law can review the traffic stop, testing procedures, and evidence involved.
Contact Blanford Law today at ken@blanfordlaw.com or 253-720-9304 for guidance on your legal matter.