Wyo. Stat. Ann. § 18-3-202

Before entering upon the duties of his office, the county assessor shall take and subscribe the following oath or affirmation: "I, .... having been elected assessor of .... county, state of Wyoming, do solemnly swear (or affirm) that I will faithfully and impartially perform the duties of assessor of the county of ...., state of Wyoming, according to law and to the best of my ability, and that I will without fear or favor assess all taxable property within the county of ...., at its fair value. So help me God".