Wash. R. Ct. Lim. Juri. CrRLJ 6.14
In any case, the court on motion of the prosecuting authority may order that a witness shall not be excused from giving testimony or producing any papers, documents or things, on the ground that such testimony may tend to incriminate or subject the witness to a penalty or forfeiture arising from the commission of a gross misdemeanor, misdemeanor, or traffic infraction; but the witness shall not be prosecuted or subjected to criminal penalty or forfeiture for or on account of any gross misdemeanor, misdemeanor, or traffic infraction concerning which the witness has been ordered to testify pursuant to this rule. If such testimony may tend to incriminate or subject the witness to a penalty or forfeiture arising from the commission of a felony, immunity may only be sought with the concurrence of the prosecuting authority in whose county the offense occurred. The witness may nevertheless be prosecuted for failing to comply with the order to answer, or for perjury or the giving of false evidence.
Wash. R. Ct. Lim. Juri. CrRLJ 6.14