Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 29, § 49B

In addition to any other security provided by laws, bonds and notes of the commonwealth may, in the discretion of the state treasurer, be secured or supported, in whole or in part, by insurance or by lines or letters of credit or other credit or liquidity facilities provided by any bank, trust company or other financial institution.

The state treasurer may enter into agreements with brokers for the placement of any such commonwealth notes issued as commercial paper.