RCW 4.44.290: Replacement juror procedure.

If after the formation of the jury, and before verdict, a juror becomes unable to perform his or her duty, the court may discharge the juror. In that case, unless the parties agree to proceed with the other jurors: (1) An alternate juror may replace the discharged juror and the jury instructed to start their deliberations anew; (2) a new juror may be sworn and the trial begin anew; or (3) the jury may be discharged and a new jury then or afterwards formed.