Wash. Rev. Code § 43.43.370
The chief of the Washington state patrol may appoint such staff or technical officers as he or she deems necessary for the efficient operation of the patrol, and he or she may assign whatever rank he or she deems necessary to such staff or technical officers for the duration of their service as such.
Staff or technical officers may be returned to their line rank or position whenever the chief so desires. Staff or technical officers without line command assignment and whose duties are of a special or technical nature shall hold their staff or technical rank on a continuing probationary basis; however, such staff or technical officers, if otherwise eligible, shall not be prevented from taking the line promotion examinations, and qualifying for promotion whenever the examinations may be held.
If a staff or technical officer returns to line operations he or she shall return in the rank that he or she holds in the line command, unless promoted to a higher rank through examination and appointment as herein provided: PROVIDED, Nothing contained herein shall be construed as giving the chief the right to demote or to reduce the rank of any officer of the patrol who was holding such office on April 1, 1949.
RCW 43.43.370