This part does not prohibit legal assistance—

(a) To challenge a conviction resulting from a criminal proceeding in which the defendant received representation from a recipient pursuant to Corporation regulations; or

(b) Pursuant to a court appointment made under a statute or a court rule or practice of equal applicability to all attorneys in the jurisdiction, if authorized by the recipient after a determination that it is consistent with the primary responsibility of the recipient to provide legal assistance to eligible clients in civil matters.