Can a defendant obtain grand jury testimony from an immunized witness?

The secrecy of grand jury testimony cannot be promised after an indictment has been returned. Defendants may obtain grand jury testimony for a number of purposes. (E. g., Dennis v. United States (1966) 384 U.S. 855, 86 S.Ct. 1840, 16 L.Ed.2d 973.) The Tierney court's confidence that "the court granting immunity could protect appellants by refusing to make their testimony available to defendants in other cases . . . " (465 F.2d at 812) is misplaced. If the immunized witness is called as a prosecution witness, the court could not prevent access to his grand jury testimony without violating the defendant's statutory and constitutional rights. Moreover, the possibility is remote that a court will refuse to disclose grand jury testimony if the price for preserving secrecy is the potential dismissal of the very indictments that the testimony was obtained to secure, or, acquittal of the same persons because the grand jury testimony was not available to them.