Our State Supreme Court decided State v. Baird, concluding breath testing without a warrant is constitutional under the Federal 4th Amendment and Article 1, Sec. 7. In the Court of Appeals case, State v. Nelson, the court analyzed the state constitution issue more closely and concluded breath testing is constitutionally valid without a warrant.
The defense sought review of that decision, but it was denied. State v Nelson - Terminating Review - - 7-11-2019.pdf The validity of breath testing in Washington is now settled law under both the Federal and the State constitutions.