Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 10, § 5C

The state treasurer shall establish an investment division, under the direction of a deputy state treasurer, for investments, who shall be responsible for the investment of all state funds under the custody of the state treasurer, including without limitation temporary cash investment.

The state treasurer may retain such professional investment counsel or other counsel to evaluate and recommend policies for cash and investment management for the commonwealth or its subdivisions.