Mich. Comp. Laws § 51.262: Chief deputy sheriff; appointment and oath of office, filing.

Sec. 2.

Such appointment shall be in writing under the hand of said sheriff and shall be filed in the office of the clerk of said county; the person so appointed, before entering upon the duties of the said office, shall take the oath prescribed in the constitution of the state of Michigan and file the same together with his acceptance, with the county clerk of said county.