(a) Any provision in an agreement or instrument which purports to relieve a fiduciary from responsibility or liability for any responsibility, obligation, or duty under this subchapter shall be void as against public policy.
(b) Nothing in this section shall preclude:
(1) The Board from purchasing insurance for its fiduciaries or for itself to cover liability or losses occurring by reason of the act or omission of a fiduciary, if such insurance permits recourse by the insurer against the fiduciary in the case of a breach of a fiduciary obligation by such fiduciary;
(2) A fiduciary from purchasing insurance to cover liability under this subchapter from and for his own account; or
(3) An employee organization from purchasing insurance to cover potential liability of one or more persons who serve in a fiduciary capacity with regard to the Fund from which the annuities and other retirement and disability benefits of the members of such employee organization are paid.