Each house shall be the judge of the election, returns and qualifications of its own members, and a majority of each house shall constitute a quorum to do business; but a smaller number may adjourn from day to day and may compel the attendance of absent members, in such manner and under such penalties as each house may provide.
Judges of Their Own Election and Qualification-Quorum
Wash. Const. art. II, § 8 — under Legislative Department.
Wash. Const. art. II, § 8
Judges of Their Own Election and Qualification-Quorum