¶1Thomas F. Gilson, Halbert, Kanter, Hirschhorn & Gilson, Philadelphia, Pa., for appellant.
¶2Anthony F. List, Asst. U. S. Atty., Philadelphia, Pa. (Louis C. Bechtle, U. S. Atty., Philadelphia, Pa., on the brief), for appellee.
¶3Before STALEY, SEITZ, and STAHL, Circuit Judges.
¶6This is an appeal from a jury conviction on three counts of aiding and abetting in the commission of a bank robbery, 18 U.S.C. §§ 2 and 2113(a), (b) and (d).
¶7Appellant, tried separately, was convicted on the basis of the testimony of one of his accomplices, Harris, who testified that appellant was to be the “wheel man”1 in the planned robbery, and the testimony of two other persons as to certain admissions made by appellant during his confinement awaiting trial.
¶8Appellant claims the trial court erred in sustaining a Government plea of surprise and permitting the Assistant United States Attorney, over objection, to cross-examine Government witness Harris.
¶9Appellant further maintains that Harris’ testimony implicating appellant in the robbery, given subsequent to the plea of surprise, was inadmissible as substantive evidence since it was allegedly adduced on cross-examination for the purpose of impeachment. Therefore, appellant asserts, the Government failed to prove a corpus delicti, thus rendering inadmissible the evidence of appellant’s admissions testified to by other witnesses.
¶10Finally, appellant claims that even if Harris’ testimony may properly be considered as substantive evidence, it was insufficient to show that appellant had any knowledge of the robbery plans and, therefore, the trial judge should have granted the motion for a verdict of acquittal.
¶11For the reasons indicated below, we find no merit in these contentions and we affirm the conviction.2
¶12We recently stated that in order for the Government properly to claim surprise, two elements must be present:
(1) the witness’ testimony … [must be] contrary to that which had been anticipated and (2) … the testimony … [must be] actually injurious to the Government’s case. United States v. Miles, 413 F.2d 34, 37 (3d Cir. 1969).
¶13While we have some doubt that in the instant case Harris’ testimony prior to the' claim of surprise had worked any affirmative injury to the Government’s case,3 under the circumstances here it is not necessary to decide whether any such injury occurred.
¶14Even assuming the ruling on surprise to have been erroneous, we find that appellant was in no way prejudiced thereby as no impeachment of Harris was actually attempted by the Government after it received permission to do so.4
¶15 Impeachment, as that term is relevant to the instant case, is the use of a witness’ prior inconsistent statements to attack his credibility and to cast doubt on the testimony he has given.5 Generally such inconsistent statements, *231whether shown by extrinsic evidence or used on cross-examination, may not be considered by the jury as substantive evidence of the truth of their contents but go only to the credibility of the witness’ in-eourt testimony.6
¶16A careful examination of the record reveals that no use was made by the Government of any inconsistent statement. Indeed, there was virtually no cross-examination even though the judge had ruled it permissible.7
¶17The ruling of surprise was made out of the presence of the jury and of witness Harris after he had given several apparently evasive answers. When the Government resumed questioning, it became apparent he was not in fact hostile and that he would testify for the Government as previously anticipated. Virtually all questions put to Harris by the United States Attorney thereafter were proper as on direct examination. Thus, the jury, which was unaware of the judge’s ruling of surprise, could not have been misled into considering impeachment evidence as substantive evidence for the simple reason that no impeachment evidence was presented.8
¶18Appellant's claim that Harris’ testimony, even if properly admitted as substantive evidence, was insufficient to show that appellant had knowledge of the robbery plans is contrary to the record. Harris’ testimony contains numerous passages indicating appellant’s prior knowledge of the robbery. Trial Transcript 132-134, 136, 139-140. This testimony, coupled with that of the other witnesses, was sufficient to sustain the trial judge’s refusal to grant a verdict of acquittal.
¶19The judgment of the district court will be affirmed.