Mich. Comp. Laws § 565.502

Sec. 2. That no compensation shall be allowed for indexing in the general index, deeds, mortgages and other instruments, that shall be left for record after the general index books shall be furnished to the registers of the respective counties, or when said books may have been already furnished, and the registers are hereby required without charge, to index all such deeds, mortgages, and other instruments in said general index.