Michigan Compiled Laws, Chapter 487. Financial Institutions § 487.14403

Sec. 4403. (1) A bank exercising a trust power as provided in this section and sections 4401, 4402, 4404, and 4405  1 shall segregate all assets held in a fiduciary capacity from the general assets of the bank, shall keep a separate set of books and records showing in proper detail all transactions engaged in under the authority of this section and sections 4401, 4402, 4404, and 4405, and at all times shall keep the bank's trust department business separate and distinct from the bank's commercial banking business.

(2) Funds, at any time and from time to time, held in trust by the bank awaiting investment or other disposition, may be commingled and consolidated, and may be deposited in other banks as designated by the board of directors or may be held at any time and from time to time by the bank under a deposit relationship and used by the bank in the conduct of the bank's individual corporate business, but only to the extent and when the bank shall set aside for the protection of the owners of the funds obligations of the United States, obligations that are guaranteed fully as to principal and interest by the United States, general obligations of this state or of any political subdivision of this state, surety bonds, or other securities approved by the commissioner equal at face value to the amount of the funds held and so used less the amount of the funds that are insured by the federal deposit insurance corporation. If the bank fails, the owners of the funds held in trust, awaiting investment or other disposition, shall have a lien on the securities set apart in addition to any other claims against the bank.