Wyo. Stat. § 1-30-105: Writ to be peremptory if right is clear; alternative writ to issue in other cases.

When the right to require the performance of the act is clear and it is apparent that no valid excuse can be given for not performing it, a court may allow a peremptory mandamus. In all other cases an alternative writ must first be issued on the allowance of the court, or a judge thereof.