could intimidate or harass potential defense witnesses to discourage them from testifying — for example, by threatening them with prosecution for perjury or other offenses. Where such intimidation tactics cause a potential witness to invoke the fifth amendment and withhold testimony that otherwise would have been available to the defendant, a court may order the prosecutor to grant immunity to the witness or face a judgment of acquittal. See, e.g., United States v. Pinto, 850 F.2d 927, 932 (2d Cir.), cert. denied, — U.S. -, 109 S.Ct. 174, 102 L.Ed.2d 143 (1988); Hooks, 848 F.2d at 799; United States v. Lord, 711 F.2d 887, 891 (9th Cir.1983); United States v. Morrison, 535 F.2d 223, 229 (3d Cir.1976). Cf. Webb v. Texas, 409 U.S. 95, 98, 93 S.Ct. 351, 353, 34 L.Ed.2d 330 (1972) (<HOLDING>). Second, the government could intentionally
holding that the defendants due process rights were violated when the trial judge singled out the only defense witness and indicated to that witness that he expected the witness to he and would personally ensure that the witness was prosecuted for perjury and thereby effectively drove that witness off the stand holding that a judges lengthy perjury warnings to a defense witness effectively drove the witness off the stand thereby denying the defendant his due process right to present his defense holding that warnings given to a witness by the trial court and the prosecutor concerning the possibility that testifying could place the witness in jeopardy of revocation of his plea agreement and charges of perjury or false statement did not violate the defendants due process rights because the warnings merely corroborated in a straightforward and nonthreatening manner the information given by the witness attorney holding right to present a defense was violated when the trial judge singled out and admonished a defense witness about the risks of perjury in unnecessarily strong terms holding that a trial judges action in singling out a defense witness for a lengthy admonition on the dangers of perjury effectively drove that witness off the stand and thus deprived the defendant of due process of law under the fourteenth amendment