(a) No action shall be brought for professional negligence against a criminal defense attorney under contract with or providing ad hoc legal services for the Office of the Defender General unless the plaintiff has first successfully prevailed in a claim for postconviction relief based upon ineffective assistance of counsel in the same or a substantially related matter. Failure to prevail in a claim for postconviction relief based upon ineffective assistance of counsel under contract with or providing ad hoc legal services for the Office of the Defender General shall bar any claim against the attorney based upon the attorney’s representation in the same or a substantially related matter.
(b) In the performance of duties pursuant to a contract with or providing ad hoc legal services to the Office of the Defender General, an attorney shall have the benefit of immunity to the same extent as an attorney employed by the Defender General.