A person executing any such commission shall be paid, out of the state treasury, the same fees that are allowed by law for the taking of depositions on commissions issued out of the superior courts of this state; and any witness attending before either house of the legislature, or any committee or joint committee thereof, or before any such commissioner, shall be so paid two dollars per day for each day in attendance, and five cents a mile for the distance necessarily traveled in attending as such witness.
RCW 44.16.110