Except as provided in G.S. 15A-905(b) this Article does not authorize the discovery or inspection of reports, memoranda, or other internal defense documents made by the defendant or his attorneys or agents in connection with the investigation or defense of the case, or of statements made by the defendant, or by prosecution or defense witnesses, or by prospective prosecution witnesses or defense witnesses, to the defendant, his agents, or attorneys.
N.C. Gen. Stat. § 15A-906