Mich. Comp. Laws § 38.846
Beginning September 1, 1981, the sum of the salary or compensation figure used by a retirement plan offered by a local unit of government subject to this act as the basis for determining a judge's retirement benefit as a member of that plan and the final salary determined for the judge pursuant to Act No. 198 of the Public Acts of 1951, as amended, being sections 38.801 to 38.830 of the Michigan Compiled Laws, or Act No. 165 of the Public Acts of 1954, as amended, being sections 38.901 to 38.933 of the Michigan Compiled Laws, if the judge is a judge of the probate court, shall not exceed the judge's total annual judicial salary payable from all sources at the time of his or her retirement. This section shall not be construed to diminish or impair an accrued financial benefit.
MCL 38.846