Cal. Government Code - GOV § 67620. Section 67620.
The holder of any bond may, for the equal benefit and protection of all holders of bonds similarly situated, do either of the following:
(a)
By mandamus or other appropriate proceedings, require and compel the performance of any of the duties imposed upon the commission or department or assumed by it, its officers, agents, or employees under the provisions of any indenture, in connection with the acquisition, construction, operation, maintenance, repair, reconstruction, or insurance of the regional transit terminal, or in connection with the collection, deposit, investment, application, and disbursement of the rates, rents, fees, charges, and other revenues derived from the operation and use of the terminal, or in connection with the deposit, investment, and disbursement of the proceeds received from the sale of bonds.
(b)
By action or suit in equity, require the commission or department to account as if it were the trustee of an express trust, or enjoin any acts or things which may be unlawful or in violation of the rights of the holders of the bonds.