Mich. Comp. Laws § 6.13: Impeachment; powers of managers, rights of process.

Sec. 13.

The managers elected by the house of representatives, shall have all necessary powers for conducting the trial of impeachments before the senate, and they, and also the person impeached, shall severally be entitled to process for compelling the attendance of persons, or the production of papers and records required for the trial of the impeachment.