The sequestration of expert witnesses in Ohio falls under Ohio’s Rules of Evidence, Rule 615. OHIO REV. CODE ANN. § 6.615 (West 2017). This rule requires the court to exclude a witness when a party requests or the court itself orders. Id. The rule provides for four exceptions, and experts fall under the third exception. Id. The third exception is for “a person whose presence is shown by a party to be essential to the presentation of the party’s cause.” Id. The notes to the rule state that while the rule requires the court to exclude a witness if requested by a party, the court maintains the ability to exercise discretion when doing so. Id.