Mich. Comp. Laws § 324.21537: Persons authorized to invest funds; authority bonds or notes as security for public deposits.

Sec. 21537.

Notwithstanding any restriction contained in any other law, the state and a public officer, local unit of government, or agency of the state or a local unit of government; a bank, trust company, savings bank and institution, savings and loan association, investment company, or other person carrying on a banking business; an insurance company, insurance association, or other person carrying on an insurance business; or an executor, administrator, guardian, trustee, or other fiduciary may legally invest funds belonging to them or within their control in bonds or notes issued under this part, and authority bonds or notes shall be authorized security for public deposits.