Gov. Code, § 31000.3

Any contract for services entered into by a board of supervisors pursuant to Section 31000 may provide for deferred payment of compensation for services rendered if (a) the terms and conditions under which payment of deferred compensation is to be made are set forth in the contract; and (b) the deferred compensation is deposited with a corporation or association authorized to conduct the business of a trust company in this state; and (c) the deposit of deferred compensation is made pursuant to the terms of a written agreement between the board of supervisors and the depository under which it is agreed that the deferred compensation shall be invested only in such investments, securities, annuities and policies of life insurance as may be agreed upon; and (d) the agreement between the board of supervisors and the depository provides that the deferred compensation and any increment thereto shall be refunded to the board of supervisors if the contractor fails to comply with the terms and conditions specified in the contract of employment.