Whenever an act or omission is declared to be unlawful in chapter 46.44 RCW, the owner or lessee of any motor vehicle involved in such act or omission is responsible therefor. Any person knowingly and intentionally participating in creating an unlawful condition of use, is also subject to the penalties provided in this chapter for such unlawful act or omission.
If the person operating the vehicle at the time of the unlawful act or omission is not the owner or lessee of the vehicle, such person is fully authorized to accept the citation and execute the promise to appear on behalf of the owner or lessee.
RCW 46.44.120