Gov. Code, § 31590

(a) All warrants, checks, and electronic fund transfers drawn on the retirement fund shall be signed or authorized by at least two board officers or employees, designated by the board or by the treasurer if designated by the board. If the treasurer is designated by the board, the board shall also designate the auditor to sign or authorize warrants, checks, and electronic fund transfers. The authorization may be by blanket authorization of all warrants, checks, or electronic fund transfers appearing on a list or register, or may be by a standing order to draw warrants, checks, or electronic fund transfers, which shall be good until revoked. If the treasurer and auditor are designated by the board, a warrant, check, or electronic fund transfer is not valid until it is signed or authorized, numbered, and recorded by the county auditor, except as provided in subdivision (c).

(b) Any person entitled to the receipt of benefits may authorize the payment of the benefits to be directly deposited by electronic fund transfer into the person’s account at the financial institution of the person’s choice under a program for direct deposit by electronic transfer established by the board or treasurer if authorized by the board. The direct deposit shall discharge the system’s obligation in respect to that payment.

(c) The board may, or, if authorized by the board, the treasurer shall, authorize a trust company or trust department of any state or national bank authorized to conduct the business of a trust company in this state or the Federal Reserve Bank of San Francisco or any branch thereof within this state, to process and issue payments by check or electronic fund transfer.