Mich. Comp. Laws § 18.1442

Sec. 442. Funds appropriated to an entity within the legislative branch of state government shall be expended or be transferred to another account only with the written approval of the authorized agent of the legislative entity. When the authorized agent of the legislative entity notifies the department of its approval of an expenditure or transfer within the existing level of appropriations, the department shall immediately make the expenditure or transfer. The authorized legislative entity agents shall be designated by the speaker of the house for house entities, the senate majority leader for senate entities, and the legislative council for library of Michigan and legislative council entities.