Mich. Comp. Laws § 773.5: Inquest; oath or affirmation to be administered witnesses.

Sec. 5.

An oath or affirmation to the following effect shall be administered to each witness by the magistrate: "You do solemnly swear, or affirm, that the evidence you shall give at this inquest, concerning the death of the deceased, shall be the truth, the whole truth, and nothing but the truth".