Notwithstanding any other provision of law, whenever any state agency, institution of higher education, or other appointing authority is empowered to employ or appoint administrators or other personnel and to fix their compensation, such power, in the absence of a specific contrary statutory authorization to the agency, institution of higher education, or appointing authority, shall not extend to the power to provide a state owned or leased motor vehicle for any use other than official state business.
RCW 43.01.150
Providing motor vehicle transportation services for public employees: RCW 43.19.560 through 43.19.635.