Cases under the Jencks Act have indicated that the Act calls not only for timely disclosure of statements, but also for the preservation of statements for future disclosure. In Campbell (I) v. United States, 365 U.S. 85, 98, 81 S.Ct. 421, 5 L.Ed.2d 428 (1961), a majority of the Supreme Court found it unnecessary to decide when destruction of possible Jencks Act material would require sanctions, but failed to adopt the minority view that the Act imposed no duty of preservation, Id. at 102, 81 S.Ct. 421. Subsequently, the Court implied there was some duty to preserve, holding that the destruction of an F.B.I. agent's notes was not impermissible as long as the data in them had been incorporated in another document and the notes had been destroyed in good faith and in keeping with general practice. Killian v. United States, 368 U.S. 231, 242, 82 S.Ct. 302, 7 L.Ed.2d 256 (1961). See also United States v. Augenblick, 393 U.S. 348, 355-56, 89 S.Ct. 528, 21 L.Ed.2d 537 (1969) (government had duty of producing tapes covered by Jencks Act, or explaining why it could not do so). Lower courts have held that the intentional destruction, even in good faith, of a government witness' statement can violate the Jencks Act and warrant sanctions. E. g., United States v. Bufalino, 576 F.2d 446, 448-50 (2d Cir.), Cert. denied, 439 U.S. 928, 99 S.Ct. 314, 58 L.Ed.2d 321 (1978) (although no sanctions imposed for the destruction of backup tapes of drug transactions, deliberate destruction of Jencks material will ordinarily call for sanctions in the future); United States v. Well, 572 F.2d 1383, 1384-85 (9th Cir. 1978) (routine destruction of interview tapes justified a mistrial and suppression of testimony), United States v. Carrasco, 537 F.2d 372, 375-77 (9th Cir. 1976) (routine good faith destruction of informant's diary called for a new trial); United States v. Bryant, 142 U.S.App.D.C. 132, 140-143, 439 F.2d 642, 650-53 (D.C. Cir.) (negligent or bad faith nonpreservation of tapes of a drug transaction might call for sanctions; remanded), Appeal after remand, 145 U.S.App.D.C. 259, 448 F.2d 1182 (1971); Lee v. United States, 125 U.S.App.D.C. 126, 129-130, 368 F.2d 834, 837-38 (D.C. Cir. 1966) (testimony of agents whose reports had been destroyed in the ordinary course of business should have been stricken); United States v. Lonardo, 350 F.2d 523, 527-30 (6th Cir. 1965) (deliberate destruction of stenographic transcripts required mistrial). Compare, e. g., United States v. Miranda, 526 F.2d 1319, 1328-29 (2d Cir. 1975), Cert. denied, 429 U.S. 821, 97 S.Ct. 69, 50 L.Ed.2d 82 (1976) (inadvertent or negligent, nonprejudicial loss of tape of drug transactions did not warrant sanctions); United States v. Perry, 153 U.S.App.D.C. 89, 94-98, 471 F.2d 1057, 1062-66 (D.C. Cir. 1972) (unintentional, nonnegligent loss of grand jury minutes would not justify sanctions; remanded).