Mich. Comp. Laws § 6.15
The presiding officer and members of the senate, while sitting as a court of impeachment, and the managers elected by the house, shall receive the sum of 5 dollars each per day, and mileage at the rate of 10 cents per mile in going from and returning to their places of residence by the ordinarily traveled routes; and the compensation of the secretary, sergeant-at-arms, and all subordinate officers, clerks, and reporters, shall be an amount as shall be established by the vote of the members of the court. The state treasurer shall, upon presentation of a certificate or certificates signed by the presiding officer and secretary of the senate pay all the expenses of the senate and managers elected by the house, which may be incurred under this act.
MCL 6.15