FEDERAL RULE OF CIVIL PROCEDURE 16(B) (2) PROVIDES AN ABSOLUTE BAR TO THE POSTINDICTMENT DISCOVERY OF A DEFENSE ATTORNEY'S WORK PRODUCT--THAT MATERIAL PREPARED IN ANTICIPATION OF LITIGATION. NO SHOWING OF SUBSTANTIAL NEED BY THE PROSECUTION MAY OVERCOME THIS PROTECTION OF THE ATTORNEY. CASE LAW INDICATES THAT THIS PROTECTION HAS BEEN EXTENDED TO THE PREINDICTMENT STAGE. THE WORK-PRODUCT DOCTRINE PROTECTS AN ATTORNEY CALLED BEFORE A GRAND JURY TO TESTIFY ABOUT HIS OR HER CLIENT. THE RATIONALE FOR THIS EXTENDED PROTECTION WAS EXPLAINED IN IN RE TERKELTOUB (1966) AS HAVING ITS BASIS IN THE RIGHT OF PRIVACY OF THE ATTORNEY AND THE RIGHTS OF DUE PROCESS AND EFFECTIVE COUNSEL FOR THE CLIENT. IN UNITED STATES V. NOBLES (1975) AND SUBSEQUENT CASES, THE WORK-PRODUCT DOCTRINE HAS BEEN CONSIDERED A VALID GROUND ON WHICH TO REFUSE A GRAND JURY'S SUBPOENA OR QUESTIONING. MATERIALS SUCH AS THE LEGAL OPINIONS, THEORIES, CONCLUSIONS, AND MENTAL IMPRESSIONS OF AN ATTORNEY HAVE BEEN HELD PROTECTED FROM DISCOVERY EVEN UPON A DEMONSTRATION OF GOOD CAUSE. CITATIONS ARE INCLUDED WITHIN THE TEXT. (TWK)