In Washington State, the (portable breath test) PBT is used by law enforcement to find probable cause to arrest for DUI or Physical Control. The PBT is administered at the scene of the DUI stop. It is not used in the case-in-chief that goes before the jury. However, it is used in Hearings challenging the arrest by the defense. That said, the Washington Administrative Code (WAC) sets out specific detailed instructions on how the test is to be administered. Any devation will compromise the PBT test. Officers often do it incorrectly. See below:
WAC 448-15-030 Test Protocol
(1) The operator shall advise the subject that this is a voluntary test, and that it is not an alternative to any evidential breath alcohol test.The operator must perform the test according to the policies and procedures approved by the state toxicologist. The operator will perform the following test protocol:
(2) The operator shall determine by observation or inquiry, that the subject has not consumed any alcohol in the fifteen minutes prior to administering the test. If the subject has consumed alcohol during that period, the officer should not administer the screening test for probable cause purposes until fifteen minutes have passed. If the subject responds that they have not consumed any alcohol in the last fifteen minutes, the officer may offer the subject the opportunity to provide a breath sample into the PBT.
(3) Ensure a blank test result is obtained.
(4) Have the subject exhale into the mouthpiece with a full and continuous exhalation.
(5) Observe the results.