The sequestration of expert witnesses falls under Washington’s Rules of Evidence, Rule 615. WASH. REV. CODE ANN. § 6-615 (West 2017). This rule allows the court to exclude a witness upon request to do so by a party or upon its own order. Id. The rule has three exceptions and experts fall under the third. Id. The third exception is for “a person whose presence is shown by a party to be reasonably necessary to the presentation of the party’s cause.” Id.