dissenting as to Parts I, II, and 111(B)(2):
Oliver North’s was a ease of epic proportions, massively publicized, for many weeks engaging the rapt attention and emotions of the nation. The panel today reverses his convictions on three separate grounds, including a remand for an “item-by-item, line-by-line” hearing on whether any bit of evidence, as yet unidentified, may have reflected exposure to North’s immunized testimony before Congress.
After studying for months the thousands of pages of transcripts and hundreds of documents produced for the grand jury and trial, I, on the other hand, am satisfied that North received a fair trial — not a perfect one, but a competently managed and a fair one. As in all trials of this magnitude, a few errors were made, but in analyzing and researching North’s claims, including the three grounds on which the Per Curiam reverses, I do not find, singly or cumula*914tively, that any of them rose to the status of reversible error. I am convinced that the essentials of a fair trial were accorded North, and that his conviction on the three Counts of which the jury found him guilty should be affirmed.
I. Use of Immunized Testimony
I dissent from the majority’s dismissal of North’s conviction on the ground that his fifth amendment right not to incriminate himself was violated by the grand jury and trial proceedings. According to my colleagues, Kastigar v. United States, 406 U.S. 441, 92 S.Ct. 1653, 32 L.Ed.2d 212 (1972), compels a “witness-by-witness[,] if necessary, ... line-by-line and item-by-item” inquiry into every piece of testimony presented to the grand and petit juries to insure that the prosecution in no way employed or relied on North’s immunized congressional testimony in obtaining his conviction, a process that would have consumed countless extra weeks or months of trial to little or no avail. In my view, a careful analysis of the Kastigar inquiry that Judge Gesell actually undertook demonstrates that North received all of the constitutional protections to which he was entitled.
A. Legal and Factual Background
1. The Kastigar Standard
Kastigar prohibits prosecution based on “information directly or indirectly derived” from compelled testimony. 406 U.S. at 453, 92 S.Ct. at 1661. The prosecution may not “us[e] the compelled testimony in any respect,” id. (emphasis in original), and bears “the affirmative duty to prove that the evidence it proposes to use is derived from a legitimate source wholly independent of the compelled testimony.” Id. at 460, 92 S.Ct. at 1665. Since “we may not infer findings favorable to [the prosecution]” as to whether its evidence was “free of taint and independently derived,” we require the district court to “make specific findings on the independent nature of this proposed evidence.” United States v. Rinaldi, 808 F.2d 1579, 1583-84 (D.C.Cir.1987).
Rinaldi also indicates, however, that when the prosecution locates and elicits the testimony of a witness without any resort to immunized testimony, no breach of Kast-igar occurs even if the witness has, in fact, been exposed to immunized statements, but testifies only according to his personal knowledge. See Rinaldi, 808 F.2d at 1583. Furthermore, according to Rinaldi, even evidence presented to a grand or petit jury that is derived from immunized statements does not pose a Kastigar problem if it is “essentially irrelevant to the government’s case.” Id. at 1584.1 The pragmatic Rinaldi approach is widely accepted in the circuits; appropriate “prophylactic measures ... which, as a practical matter, as distinguished from absolute theoretical certainty, ensure that the evidence to be used at trial was untainted” are deemed sufficient to meet Kastigar’s standards. United States v. Poindexter, 727 F.Supp. 1488, 1492 (D.D.C.1989); see, e.g., United States v. Serrano, 870 F.2d 1, 17 (1st Cir.1989); United States v. Crow-son, 828 F.2d 1427, 1430 (9th Cir.1987), cert. denied, 488 U.S. 831, 109 S.Ct. 87, 102 L.Ed.2d 63 (1988); United States v. Byrd, 765 F.2d 1524, 1529 (11th Cir.1985).
Use of immunized material that the trial court finds to be harmless beyond a reasonable doubt is also, in many circuits, consistent with Kastigar’s strictures; indeed, a trial judge’s finding of such harmless use will be upheld if substantial untainted evidence is presented to the jury and the reference to immunized material is only tangential to the indictment or conviction. Serrano, 870 F.2d at 16 (citing cases). This court, like other courts of appeal, af*915fords trial judges substantial latitude in selecting procedures to ensure that a defendant receives his full Kastigar protections. United States v. De Diego, 511 F.2d 818, 824 (D.C.Cir.1975); see also United States v. Dynalectric, 859 F.2d 1559, 1578-80 (11th Cir.1988), cert. denied, — U.S. -, 109 S.Ct. 1642, 104 L.Ed.2d 157 (1989). In general, the options at the judge’s disposal include a pretrial evidentia-ry hearing; a taint hearing during trial if questionable evidence is offered; a post-trial taint hearing; or a combination of the foregoing. De Diego, 511 F.2d at 824.
2. Kastigar Procedures Followed in This Case
The grand jury in this case began hearing testimony on February 4, 1987. North received his immunity order on June 3, 1987, and testified before Congress from July 7 to July 14, 1987. The grand jury recessed from June 29 to September 2, 1987, and concluded taking testimony on March 14, 1988. North was indicted on March 16, 1988.
After North’s indictment, Judge Gesell first conducted a “preliminary” Kastigar hearing on April 25,1988 into the “administrative procedures” implemented by the Independent Counsel (“IC”) to avoid exposure by the IC staff to immunized testimony. Transcript of Pretrial Hearing, Apr. 12, 1988, at 3; Transcript of Pretrial Hearing, Apr. 25,1988, at 372. In his Memorandum Opinion of June 16, 1988, Judge Gesell explained that after this hearing, he reviewed in camera grand jury transcripts and exhibits; precautions taken by the IC to avoid taint from exposure of the prosecution to publicity and immunized testimony; exhibits illustrating the implementation of these precautions; and two bound volumes establishing the IC’s independent “leads” to all significant witnesses. United States v. Poindexter, 698 F.Supp. 300, 307-08 (D.D.C.1988) (hereinafter cited as Kastigar Memo). Judge Gesell’s description of these volumes as “leads” is far too modest, for they actually consist of summaries, often quite detailed, of interviews conducted by FBI agents in late 1986 and early 1987 — well before North’s immunized testimony — with over eighty key players in the Iran-Contra Affair. See Oral Argument Transcript (“Oral Arg. Tr.”) 72. In many instances, these summaries present a comprehensive precis of the witnesses’ subsequent grand jury testimony. These volumes, then, provided Judge Gesell with the necessary documentation demonstrating that the prosecution knew the vast bulk of the substance of its case before the grand jury began sitting, and certainly well before congressional immunity grants were issued. Even more extensive evidence compiled by the IC before North’s immunized testimony was “separated and sealed to ensure a full record of [the IC’s] independent development of facts and witnesses should that be necessary in more detail at a further post-trial Kastigar hearing.” Kastigar Memo, 698 F.Supp. at 313.2 Judge Gesell also examined the voir dire of two replacement grand jurors; interviews of Richard Secord conducted by the IC between April 29, 1987 and March 12, 1988; correspondence between the IC and Congress with regard to use immunity; and redacted newspaper clippings and congressional committee testimony made available to the IC’s staff. Id. at 315-16.
The court’s review of the grand jury transcripts focused on
(1) The nature and extent of the instructions given the grand jurors designed to prevent exposure to defendants’ immunized testimony.
(2) Any departure from these instructions suggested by questions or comments of counsel or jurors.
(3) Safeguards and techniques adopted by Independent Counsel to prevent inadvertent or derivative exposure of immune testimony by witnesses appearing before the grand jury.
Id. at 308-09. The court cited at some length the warnings against exposure to *916immunized testimony given by the IC to the grand jury, including Independent Counsel Walsh’s own statement to the grand jury on July 1, 1987 that
[Y]ou must, at really great expense and great inconvenience, avoid learning what Colonel North said.... I am asking you to impose on yourself the instructions you have imposed on yourselves ever since Mr. Hakim testified, but I want to reassert its importance now of avoiding reading anything about this investigation.
Id. at 310. At the time of Hakim’s immunized testimony, the IC had instructed the grand jurors not to read any newspaper or magazine articles, or listen to any television or radio reports that mentioned Hak-im. Id. at 309. Judge Gesell cited several illustrations of the grand jurors’ attentiveness to these precautions and of their “tenacious desire to avoid ... exposure.” Id. at 311-12.
The judge found that “the great bulk of the evidence was clearly known to Independent Counsel before any defendant received use immunity.” Id. at 311. Nonetheless, he pointed out that the Associate Independent Counsel gave the following specific instruction to all grand jury witnesses appearing after North’s immunized congressional testimony:
Certain witnesses have testified under Congressional grants of limited immunity before House and Senate Committees investigating the Iran/Contra matter. These witnesses include ... Oliver North_ Our Office is avoiding exposure to the immunized testimony of these witnesses I have just named. Please make sure that your answers to our questions are based solely on your own personal knowledge and recollection of the events in question. Do not relate to us anything which you learned for the first time as a result of listening to or reading or hearing about immunized testimony.
Id. at 311-12. Furthermore, the trial judge noted that the prosecution was careful to avoid rambling questions inviting generalized answers, and grand jury witnesses were temporarily excused while the IC previewed grand jurors’ questions for the witnesses, in order to ensure that their inquiries would not inadvertently elicit immunized testimony. Id. at 312.
Judge Gesell also reviewed the “administrative steps” taken by the IC to avoid exposure to immunized testimony, including the so-called Douglass File, in which all incidents of exposure involving members of the IC’s staff were recorded. The judge found that nearly all of those occurrences were inadvertent or unimportant, and concluded that “the file reflects a scrupulous awareness of the strictures against exposure and a conscientious attempt to avoid even the most remote possibility of any impermissible taint.” Id. at 313.
Judge Gesell thus concluded that North’s immunized testimony “was not submitted to the grand jury in any form”; the grand jurors were “effectively warned” not to expose themselves to the immunized material; the immunized testimony “did not serve to enhance the focus of Independent Counsel’s investigation”; and the IC and his staff were not exposed to the immunized materials and had already learned the identities and prospective testimony of all significant witnesses long before the immunized testimony was given. Id. at 314-15. On that basis, Judge Gesell reported before trial that:
Nothing has developed in the Court’s preliminary inquiry into Kastigar and related problems which suggests the defendants who received use immunity have had their Fifth Amendment rights impaired in a manner that significantly affects their right to a fair trial.
Id. at 314.
In preparation for North’s trial, Judge Gesell excused on voir dire all prospective jurors who had any substantial recollection of North’s immunized testimony. He also warned the jurors not to read or listen to news about the case until their service was complete. Voir Dire Transcript at 4. During the trial, he instructed each witness that his or her testimony had to be based solely on personal knowledge, and should in no way be influenced by incidental expo*917sure to North’s congressional testimony. He directed witnesses who were unsure whether they could distinguish personal recollection from the immunized material not to answer the question posed. See, e.g., Trial Transcript (“Tr.”) 1978-79, 3268. After the trial, he instructed the jury to base its verdict solely on record evidence. Joint Appendix (“J.A.”) 596-97.
The judge denied North’s post-trial motion for another Kastigar hearing on the grounds that the motion “raises few new issues” and “seeks in most instances to relitigate issues already resolved by the Court_” United States v. North, Cr. No. 88-0080-02, 1989 WL 57487 (D.D.C. May 26, 1989) (order). He did, however, order the disclosure to North and his counsel of the following materials on which he had based his pretrial Kastigar opinion: nontestimonial portions of grand jury proceedings transcribed at the court’s request; the Douglass file; the two volumes of materials establishing the IC’s independent “leads,” including summaries of interviews with witnesses it planned to call in its casein-chief; the transcript of voir dire of two replacement grand jurors; and an index of subpoenas issued during the investigation. In addition, he ordered the three Associate Independent Counsels who conducted the trial to “file an affidavit stating what steps each took before and during trial to avoid direct or indirect knowledge of North’s immunized testimony and [to] identify any significant exposure that may have occurred inadvertently or otherwise.” Id. Finally, Judge Gesell denied North’s motion to reconsider his decision not to hold a post-trial Kastigar hearing. United States v. North, Cr. No. 88-0080-02 (D.D.C. June 30, 1989) (order).
3. Proper Scope of Inquiry on Review
This court’s task on appeal is to determine whether Judge Gesell committed clear error in finding that there was no use of North’s immunized testimony made by the IC that infringed North’s fifth amendment rights. See Serrano, 870 F.2d at 16. We must decide whether the extensive measures taken by Judge Gesell to comply with Kastigar effectively ensured that the IC made no significant direct or indirect evi-dentiary use of North’s immunized testimony. See Byrd, 765 F.2d at 1529. This, not the absence of a “witness-by-witness ... line-by-line and item-by-item” Kastigar hearing, should be the crux of our inquiry.
B. Grand Jury Proceedings
The majority expends enormous time and effort attempting to validate North’s claim that the prosecution’s wrongful use of immunized testimony caused “the grand jury no longer to be a grand jury,” Midland Asphalt Corp. v. United States, 489 U.S. 794, 109 S.Ct. 1494, 1499-1500, 103 L.Ed.2d 879 (1989), because such use constituted the kind of “fundamental” defect in the grand jury process that could ultimately require quashing the indictment. See Per Curiam at 871. If such use had occurred in any purposeful or even accidentally harmful way, I would not disagree with the majority’s legal premise: The “rule” that “a facially valid indictment need not be dismissed solely because the grand jury has considered evidence that would be inadmissible at trial” does not apply to use of immunized testimony. Id. at 869. See United States v. Calandra, 414 U.S. 338, 94 S.Ct. 613, 38 L.Ed.2d 561 (1974); United States v. Blue, 384 U.S. 251, 86 S.Ct. 1416, 16 L.Ed.2d 510 (1966); Lawn v. United States, 355 U.S. 339, 78 S.Ct. 311, 2 L.Ed.2d 321 (1958); United States v. Costello, 350 U.S. 359, 76 S.Ct. 406, 100 L.Ed. 397 (1956). As my colleagues properly point out, Kastigar’s prohibition of the prosecution’s direct or indirect “use” of immunized testimony goes to the heart of the grand jury process and renders an indictment so obtained a “constitutional and statutory transgression.” Per Curiam at 869.
But nothing like that happened here. As Judge Gesell found, none of the grand jury testimony “became known” to the IC “either from the immunized testimony or from leads derived from the testimony, directly or indirectly.” Kastigar Memo, 698 F.Supp. at 315-16. The judge examined the IC’s “leads,” which, as I have already explained, included substantive summaries *918of FBI interviews that mirrored subsequent grand jury testimony. Thus, the judge knew from these summaries that long before North testified before Congress, the few witnesses relevant to Counts 6, 9, and 10 — the Counts on which North was ultimately convicted — who appeared before the grand jury after North testified before Congress had already presented the essential elements of their eventual grand jury testimony to the IC. On the strength of those interview summaries, which documented the witnesses’ personal involvement in the key events relevant to the conviction Counts, the judge properly found that the prosecution carried its burden under Kastigar of proving that North’s indictment was not tainted by improper use of his immunized testimony.3 It is indeed striking that North’s counsel cannot point to a single instance of alleged witness testimony tainted by exposure to North’s immunized testimony to challenge Judge Gesell’s conclusion that no breach of Kastigar occurred at the grand jury stage.
1. Content of Witness Testimony
My colleagues’ basic criticism of the trial judge’s post-indictment Kastigar inquiry centers on “the government’s possible use of compelled testimony via the grand jury and trial witnesses.” Per Curiam at 872. The trial judge, however, expressly ruled that he found no such use, and we must defer to his finding, provided that it was not clearly erroneous. See Serrano, 870 F.2d at 16; Crowson, 828 F.2d at 1429. To reach his holding, Judge Gesell reviewed the content of grand jury transcripts and exhibits in light of the IC’s independent prior “leads” to its witnesses, summaries of the substance of their likely grand jury testimony, and an index of subpoenas issued during the IC’s investigation. Kastigar Memo, 698 F.Supp. at 315-16. This documentation strongly supported the judge’s ruling. Judge Gesell also cited the emphatic instructions given to grand jurors to avoid exposure and the warnings to all grand jury witnesses appearing after North’s immunized testimony to Congress that they must testify from personal recollection only. The judge found as well that the narrow format of the prosecution’s questions during the grand jury proceedings was conducive to avoiding revelations of immunized testimony,
Of decisive importance, moreover, is the fact that nearly all of the grand jury witnesses testifying with regard to Counts 6, 9, and 10 appeared before North presented his immunized testimony to Congress. Indeed, Judge Gesell noted in his Kastigar Memo “the fact ... that the great bulk of the evidence was clearly known to Independent Counsel before any defendant received use immunity....” 698 F.Supp. at 311. Corroborating this conclusion, the IC represented at oral argument that the testimony relevant to Counts 6, 9, and 10 was presented before North’s immunized testimony. Oral Arg. Tr. 56. Although North’s counsel correctly pointed out that “many” grand jury witnesses did not appear until after the immunized testimony, id. at 20, he did not dispute the IC’s basic characterization of witnesses appearing after North’s immunized testimony as irrelevant to the Counts on which he was convicted. And the law in this circuit is clear that even evidence derived from immunized statements does not pose a Kasti-gar problem if it is irrelevant to the prosecution’s case. See Rinaldi, 808 F.2d at 1584.
Neither North nor the IC provided us with a precise count or description of the grand jury witnesses appearing after North’s immunized testimony who testified with regard to Counts 6, 9, and 10. This is the only subset of witnesses, however, whose testimony poses even potential Kast-igar problems. Rather than attempting to identify these witnesses, the Per Curiam *919instead relies heavily on papers filed by the defense indicating that senior officials and attorneys at the Department of Justice, the Central Intelligence Agency, the White House, and the Department of State gathered, studied, and summarized North’s immunized testimony to prepare themselves and their colleagues for grand jury testimony. See Per Curiam at 863. My colleagues make no attempt to demonstrate to what extent the grand jury testimony of any of these individuals was relevant to the Counts at issue.4
A reading of the relevant grand jury transcripts reveals that only the testimony given by two highly placed Justice Department officials, relevant to Count 6 alone, could possibly raise Kastigar difficulties. Each witness’ testimony was essentially cumulative of the other’s, and both concerned a key meeting that they attended critical to North’s role in preparing a false chronology for CIA Director Casey’s testimony to Congress. One of the two witnesses, however, had already described North’s actions in developing the false chronology in similar terms in his FBI interview recorded in the volumes of the IC’s “leads” examined by Judge Gesell. The judge expressly stated in his Kastigar Memo that he “relied on” the two bound volumes of “leads” containing the summary of this interview.5 Thus, the district court knew that the critical evidence had been conveyed by at least one witness before North’s immunized-testimony, regardless of the timing of the witnesses’ grand jury appearances.6 Furthermore, the content of these witnesses’ grand jury testimony provides the necessary basis for concluding that they testified from personal recollection; indeed, their recollection of this meeting corroborated North’s own trial testimony about his role in preparing the false chronology. Cf. Rinaldi, 808 F.2d at 1583 (no breach of Kast-igar if witness testifies solely based on personal recollection, despite exposure to immunized testimony). Neither witness contradicted North’s own account in any significant way; and it strains credulity to say that by calling these witnesses, the IC used North’s immunized testimony “against” him. Those officials, moreover, like all other grand jury witnesses, were directly warned by the IC to answer questions solely on the basis of personal knowledge, without relying in any way on immunized testimony.
Having established the independent derivation and lack of taint of this evidence, the IC met its obligation under Kastigar. 406 U.S. at 460, 92 S.Ct. at 1664 (prosecution must demonstrate that “evidence it proposes to use is derived from a legitimate source wholly independent of the compelled testimony” (emphasis supplied)). Thus, while a “line-by-line, item-by-item” adversary Kastigar hearing might have *920given .North’s counsel an occasion to grill these officials further on the source of their testimony, it is highly unlikely that such a hearing would have helped North’s cause in light of the IC’s documentation of its independent development of the substance of their testimony. As to other testimony relevant to Count 6, and testimony pertinent to Counts 9 and 10, the key witnesses with crucial firsthand knowledge, subsequently corroborated by North’s own trial testimony, appeared before the grand jury before North presented his immunized testimony to Congress.
To sum up: The record is clear that at most only a negligible amount of testimony relevant to the conviction Counts was presented to the grand jury after North testified to Congress under immunity. One of the few witnesses presenting that testimony — which, by my reading, was relevant only to Count 6 — had already revealed the key facts to the IC through the FBI interviews conducted long before North’s congressional appearance. Documentation of the IC’s prior knowledge of these witnesses’ testimony was presented to Judge Ge-sell through the volumes of independent “leads.” Additionally, the witnesses were adequately warned by the IC not to rely on any exposure to immunized testimony, and they testified about events in which they were pérsonally and directly involved. And their testimony merely confirmed North’s own, neither adding anything new nor contradicting his account of a critical meeting. Finally, so far as I can tell, the remainder of the grand jury testimony' relevant to Count 6 and the entirety of the grand jury testimony relevant to Counts 9 and 10 were presented before North’s congressional appearance.
The Per Curiam seems to argue that, nonetheless, it is necessary to vacate North’s convictions because the trial judge did not enforce strictly enough the government’s burden to show the absence of any indirect use of immunized testimony. But, there was nothing for the government to show, since the IC had already demonstrated, through its compendium of leads and through the grand jury testimony obtained before North’s congressional appearance, that it had come upon the information critical to the conviction Counts well before North’s immunized testimony. Although by no means determinative to the issue of whether North was prejudiced, I cannot help noting the irony of dismissing North’s conviction not because the IC employed immunized testimony in locating or questioning witnesses but solely because high Justice Department officials were exposed to the testimony by their own inside counsel.7
In sum, the witnesses testifying before the grand jury with regard to North’s conviction Counts either appeared before North’s immunized testimony or had long before presented crucial evidence against North to the FBI. Consequently, I cannot accept the Per Curiam’s insistence on vacating North’s conviction because of any “use” of his immunized testimony before the grand jury.8
*9212. Refreshment of Witness Recollection
Aside from the question of whether grand jury witnesses directly conveyed the substance of North’s immunized testimony to the grand jury (they did not), the majority insists that a full-fledged Kastigar hearing was indispensable to establish “the use of immunized testimony ... to augment or refresh recollection....” Per Curiam at 860. I agree with my colleagues that the trial judge improperly suggested that refreshment of a witness’ memory is not an evidentiary problem and can never pose Kastigar difficulties as long as the witness’ testimony remains truthful. See id. at 861. The content of witness testimony, not its truth or falsity, must be our concern under Kastigar. The majority, however, contends that the judge’s mistaken conclusion that Kastigar does not apply to refreshment of witnesses’ recollection fatally flaws his finding that “[djefendants’ immunized testimony was not submitted to the grand jury in any form.” Kastigar Memo, 698 F.Supp. at 314. I disagree strongly with that inference. The only harm that could have befallen North as a result of the refreshment of witnesses’ recollection by immunized testimony would have had to come in the form of actual statements made by the witnesses before the grand and petit juries. Here, the judge controlled for any behind-the-scenes “refreshment” of grand jury witnesses with immunized testimony by monitoring the content of their actual testimony. He examined the “leads” containing summaries of prior FBI interviews as well as the clear warnings given to the witnesses, under oath, to testify only from personal recollection, and thereby was able to ascertain that the witnesses testifying after North’s immunized testimony had informed the FBI of all of the information underlying the Counts on which North was subsequently convicted well before North’s immunized testimony. Thus, the judge ensured that witnesses did not simply relay North’s immunized testimony. In this context, refreshment of grand jury witnesses could have violated North’s fifth amendment rights in only two possible scenarios, neither of which ever actually occurred.
First, if North’s immunized testimony triggered a witness’ own recollection of events that he had otherwise forgotten, North’s testimony might be said to have been “used” to violate his right against self-incrimination. But the only two grand jury witnesses in this case whose testimony after North’s immunity grant could even conceivably have raised a Kastigar problem testified that they attended a crucial meeting involved in Count 6; the possibility that their recollections were triggered by North’s immunized testimony, rather than their own memories and records, defies credibility, especially since one of them informed the FBI — and, by extension, the IC — in detail about North’s role at the meeting well before North presented his immunized testimony.
Alternatively, the IC would have violated Kastigar by directly presenting North’s immunized testimony to grand jury witnesses in order to refresh their memories. Judge Gesell found, however, that “[pjrosecuting personnel were sealed off from exposure to the immunized testimony itself and publicity concerning it.” Kastigar Memo, 698 F.Supp. at 312. The Per Curiam itself affirms the judge’s finding. Per Curiam at 859. Nothing suggests that the IC at any time showed the immunized testimony to witnesses to refresh their recollections.
Thus, my colleagues vacate North’s convictions on the speculative basis that witnesses’ recollection may have been refreshed with his immunized testimony even though those witnesses had long before presented the same evidence they later gave the grand jury or at trial. This ruling is inconsistent with this court’s prior teaching that Kastigar does not necessarily require the reversal of a conviction merely because a grand jury witness was exposed to immunized testimony. Rinaldi, 808 F.2d at 1583. Indeed, it turns the properly “heavy” burden of proof imposed by Kasti-gar into an impenetrable hurdle that the prosecution can never overcome.
3. Grand Juror Exposure
The only remaining Kastigar problems at the grand jury stage revolve around *922possible exposure of grand jurors or members of the Independent Counsel staff to North’s immunized testimony. The majority itself, however, upholds the trial judge's findings vis-a-vis the precautions taken by the IC “to prevent untoward exposure or use by his staff.” Per Curiam at 860. As to the grand jurors, the majority says that its concern about their exposure to North’s congressional testimony “underscore^] our conclusion” that a Kastigar hearing is necessary. Id. at 872. Fortunately, the majority does not “extend [its] holding [to] require an unprecedented Kastigar-type hearing concerning possible exposure of individual grand jurors through the media,” id., for Judge Gesell’s findings show beyond the shadow of a doubt that any incidental grand juror exposure to immunized testimony did not infringe North’s constitutional rights.
The original grand jurors were seated long before North appeared before Congress. They were duly warned to avoid exposure to North’s immunized testimony; Judge Gesell found that they tried diligently to adhere to these instructions. Only one of the replacement grand jurors seated after North’s testimony said at voir dire that she saw “some but not a lot” of North’s immunized testimony, J.A. 3277 (classified appendix); she also stated, however, that she had no “fixed opinions” and had reached no conclusions that would make it difficult for her to analyze fairly the evidence before the grand jury, id. The repeated warnings given to all of the grand jurors, together with evidence of the grand jurors’ “attentive[ness]” to those instructions, Kastigar Memo, 698 F.Supp. at 311-12, support the trial judge’s determination that North’s immunized testimony “played no part in the grand jury’s unanimous decision to indict,” id. at 315; certainly, that determination was not clearly erroneous.
Thus, we all agree that no reason has been given or necessity shown for a Kasti-gar remand as to grand juror exposure.
C. Trial Stage
My colleagues and I are also in agreement that the trial judge has substantial discretion in fashioning procedures to determine whether the prosecution’s evidence at trial conforms to Kastigar. North’s counsel cites no case in which a court has required a trial judge to follow a specific procedure for compliance. Thus, while a judge who holds a pretrial hearing is not excused from guarding against taint during trial, no precedent compels that judge to conduct another full-blown post-trial hearing. The judge is responsible only for ensuring that the government bears its burden of proving that “the evidence it proposes to use is derived from a legitimate source wholly independent of the compelled testimony.” Kastigar, 406 U.S. at 460, 92 S.Ct. at 1665.
As indicated in Part A(2), supra, the trial judge here took vigorous precautions to ensure that the IC carried his burden of showing lack of taint at trial. Through written and oral questioning, Judge Gesell inquired into the exposure of prospective trial jurors to North’s immunized testimony, and instructed trial witnesses either to testify from personal knowledge or, if they were unsure of the source of their recollection, not to answer the questions put to them. See supra, at 916. After presiding at the twelve-week trial, Judge Gesell found that North’s motion for a post-trial Kastigar hearing “presented] no new information that would justify changing the Court’s [Kastigar Memo ].” United States v. North, Cr. No. 88-00080-02, 1989 WL 57487 (D.D.C. May 26, 1989) (order). The judge reasonably concluded that the trial testimony of witnesses substantially mirrored their grand jury testimony, which he had previously read and which, so far as the conviction Counts were concerned, had been given almost entirely — and was in substance fully known to the IC — prior to North’s immunized testimony.9 Absent, then, any significant difference in content between witness testimony given at the *923grand jury and at trial, Judge Gesell understandably felt that a post-trial Kastigar hearing would serve no purpose. While North, of course, did not bear the burden of proof on the Kastigar issue, it is striking that his counsel does not cite to even a single line of trial testimony that indicates either a change from the witness’ grand jury testimony or any other evidence of taint. Although the majority now throws down the gauntlet of a “line-by-line and item-by-item” Kastigar hearing, it is difficult to conceive that in the absence of a specific challenge by North, the IC could not easily have met its burden by simply submitting a post-trial statement certifying that the substance of the trial testimony did not differ from the substance of the grand jury testimony, which the trial judge had found to be untainted after a substantial inquiry. That the trial judge did not insist that the IC take such pro forma action should not require dismissal of North’s conviction.
“[I]ndulg[ing] assumptions favorable to the government” is improper in the Kasti-gar context; for that reason, we direct trial judges to make specific findings as to the admissibility of the allegedly tainted evidence. Rinaldi, 808 F.2d at 1584. But here, the district court had already made an omnibus finding that the “[defendants’ immunized testimony was not submitted to the grand jury in any form.” Kastigar Memo, 698 F.Supp. at 314. As I have already pointed out, see supra at 921, that finding is legally sound because the judge acted affirmatively to ensure that the witnesses did not transmit North’s immunized testimony to the grand jury. He ascertained that the witnesses themselves had already provided the FBI with the evidence critical to the conviction Counts before North’s testimony and that they were testifying about personal involvement in all of the events that were critical to those Counts. Additionally, the IC had been sealed off from exposure to the immunized testimony. Given that comprehensive finding of no taint in the grand jury proceedings, the judge’s post-trial determination that “no new information” was presented at trial does not “indulge assumptions favorable to the government”; rather, it affirms an earlier factual finding in a new context. Having passed muster at the grand jury phase, the government simply has nothing left to prove once the trial judge finds that the trial record contains no evidence of direct or indirect evidentiary use of immunized testimony. In that context, my colleagues’ conclusion requiring a full-blown post-trial Kastigar hearing for every jot and tittle of every witness’ testimony strikes me as not only unnecessary but as an absolute deterrent to any prosecution after a grant of immunity in a high-profile case.
It is especially puzzling that the Per Cu-riam points to the trial testimony of Robert McFarlane as “emblematic of ... the necessity of further Kastigar inquiry.” Per Curiam at 864. McFarlane testified twice before Congress, revising his original testimony after North presented his own immunized testimony. In determining that the trial testimony presented “no new information” vis-a-vis the grand jury testimony, Judge Gesell obviously compared the substance of McFarlane’s presentations before the grand jury and at trial.10 So long as McFarlane’s trial testimony was consistent with his grand jury testimony, presented before North testified in Congress, what McFarlane told Congress subsequently, on either his first or second appearance, is totally irrelevant to the Kastigar question. McFarlane’s two-step conduct before Congress may bear on his credibility, but it provides no support for the Per Curiam’s Kastigar argument.
My colleagues apparently do not reach North’s contention that petit juror exposure to the immunized testimony also violated Kastigar. In fact, the record indicates that the trial judge conducted an oral *924voir dire on the heels of an exhaustive written questionnaire to prospective jurors, and that the trial jurors who had seen or heard North’s immunized testimony were exposed only minimally. The record thus supports the trial judge’s conclusion that their exposure was harmless to North.
D. Conclusion
The Per Curiam’s insistence on a “line-by-line, item-by-item” Kastigar hearing represents an overblown interpretation of the Kastigar case that is totally unnecessary to protect North’s constitutional rights. Requiring a new and comprehensive “Kastigar hearing” this late in the game ignores the many other reasonable avenues used by Judge Gesell to protect North from any aftereffects from his congressional immunization, including his review of the prodigious efforts by prosecutors and grand and petit jurors to avoid exposure, his comparison of the substance of grand jury and trial transcripts, and his attention to the actual sources of prosecution leads and interviews with key witnesses obtained before North’s immunized testimony. The majority effectively cuts off the trial judge’s discretion in choosing the most practical means of ensuring a defendant’s Kastigar rights, and in so doing it makes a subsequent trial of any congres-sionally immunized witness virtually impossible.
While national television coverage should not be allowed to impinge on North’s statutory and constitutional rights, neither does it entitle North to escape zealous but fair prosecution. Kastigar’s strictures must be applied in a manner that protects a defendant’s constitutional rights, but also preserves the public’s interest in conducting prosecutions of officials whose crimes have far-flung implications for national policy. We require trial judges to conduct fair trials, not perfect ones, McDonough Power Equipment, Inc. v. Greenwood, 464 U.S. 548, 553, 104 S.Ct. 845, 848, 78 L.Ed.2d 663 (1984). North has failed to identify a single suspected Kastigar violation in the thousands of pages of grand jury and trial testimony, other than the misguided efforts of in-house Justice Department officials to use his immunized testimony to brief witnesses who essentially corroborated his own version of events, and who swore under oath that their ultimate testimony was derived from personal recollection only. When an “ex parte review in appellate chambers,” Per Curiam at 867, yields a clear result that is entirely consistent with the trial court’s own findings, a remand for further lengthy hearings is unjustified. I cannot conclude that Judge Gesell’s prodigious and conscientious efforts to protect North’s fifth amendment rights were in any way so ineffectual as to require a reversal on the formalistic grounds that the majority advances.
I can find no basis for vacating North’s conviction on self-incrimination grounds.
II. Necessity FOR a Specific Unanimity Instruction
I do not believe that the trial judge committed reversible error by refusing to accede to defense counsel’s request to instruct the jury on the need for unanimity on the specifics of Count 9, under which North was convicted of willfully destroying, altering, and removing official documents.
As a rule, a general instruction on unanimity, advising the jury that its members must agree unanimously on all of the essential facts necessary to a guilty verdict, sufficiently protects the defendant’s right to a unanimous jury decision, “even when an indictment count provides two or more factual bases ... upon which a conviction could rest.” United States v. Duncan, 850 F.2d 1104, 1113 (6th Cir.1988), cert. denied sub nom. Downing v. United States, — U.S. -, 110 S.Ct. 732, 107 L.Ed.2d 751 (1990) (citing cases); Fed.R.Crim.P. 31(a) (establishing right to unanimous verdict). Although this court has “urge[d]” trial judges to employ particularized instructions on specific unanimity when one charge encompasses several distinct incidents, United States v. Mangieri, 694 F.2d 1270, 1281 (D.C.Cir.1982), we have never found the absence of such an instruction to *925be error.11 Indeed, we have stressed the need to consider jury instructions “as a whole, rather than as isolated passages.” Id. at 1280 (quoting United States v. Martin, 475 F.2d 943, 947 (D.C.Cir.1973)); United States v. Hubbard, 889 F.2d 277, 279 (D.C.Cir.1989).
When jury instructions are otherwise appropriate, a particularized instruction has been found to be necessary only when
(1) the nature of the evidence is exceptionally complex or the alternative specifications are contradictory or only marginally related to each other; or (2) there is a variance between indictment and proof at trial; or (3) there is tangible indication of jury confusion, as when the jury has asked questions or the court has given regular or supplementary instructions that create a significant risk of nonunanimity.
Duncan, 850 F.2d at 1114; see also United States v. Beros, 833 F.2d 455, 460 (3d Cir.1987) (describing situations requiring specific unanimity instruction). This case, however, involves neither (3) a tangible indication of jury confusion, compare Duncan, 850 F.2d at 1114 (jury request for clarification illustrates error in failure to provide specific unanimity instruction), nor (2) insufficient evidence as to an act charged, compare United States v. Natelli, 527 F.2d 311, 325 (2d Cir.1975), cert. denied, 425 U.S. 934, 96 S.Ct. 1663, 48 L.Ed.2d 175 (1976) (general unanimity instruction improper in face of possibility that guilty verdict based on specification backed by insufficient evidence). North’s claim of error, therefore, must rest on (1) the supposed complexity of the evidence surrounding the three instances of document destruction, alteration, and removal at issue in Count 9.
Yet the evidence concerning these incidents was entirely of one piece and in no way likely to produce conflicting fact determinations by the jury members. As North admitted that he destroyed, altered, and removed all of the official documents as charged, individual jurors hardly could have believed that North did not actually commit any one of those acts. Furthermore, as to each of the alleged illegal acts, North raised some form of an “authorization defense” — Casey’s order to destroy the Contra operating fund ledger, Tr. 7138-39, McFarlane’s order to alter the official National Security Council (“NSC”) System IV documents, Tr. 6903-07, and Secord’s counsel’s advice to remove the documents from the NSC, Tr. 7109-13 — in order to prove that he did not consider his actions unlawful. The similarity of these defenses makes it highly improbable that individual jurors would have found any one of them exculpatory but not the others.
Thus, unlike complex charges requiring the jury to consider allegations of separate criminal acts committed by several people in widely differing circumstances, see, e.g., United States v. Payseno, 782 F.2d 832, 836-37 (9th Cir.1986) (requiring specific unanimity instruction when indictment alleges three different acts of extortion committed by different people in two different states over nine-month period), Count 9 compelled the jury to judge only a single individual who admitted performing interrelated criminal acts over a relatively short timespan. As general unanimity instructions have regularly sufficed in similar circumstances, see, e.g., United States v. Schiff, 801 F.2d 108, 114-15 (2d Cir.1986), cert. denied, 480 U.S. 945, 107 S.Ct. 1603, 94 L.Ed.2d 789 (1987) (single defendant concedes he filed no tax returns for three years; since only issue is his intent, general unanimity charge sufficed); United States v. Frazin, 780 F.2d 1461, 1468 (9th Cir.), cert. denied, 479 U.S. 844, 107 S.Ct. 158, 93 L.Ed.2d 98 (1986) (general instruction suffices when indictment alleges “one unified scheme to defraud”), I do not believe that the trial judge’s refusal to provide a specific unanimity instruction on Count 9 at North’s request was reversible error. Indeed, in discussing other Counts involving multiple bases for conviction, the judge told the jury earlier in the charge *926that it must decide with specific unanimity on which acts, formed the basis of its verdict. It is unlikely that his silence on this one Count would be construed to mean that such particularized unanimity was not necessary. See J.A. 620 (Count 1), J.A. 627 (Counts 2, 3, and 4). Nonetheless, in light of Mangieri’s “urgpng],” I agree with my colleagues that particularized instructions should be given in a retrial of Count 9, if one - takes place.
III. Authorization
North was convicted on Count 9 of violating 18 U.S.C. § 2071(b) by destroying, altering, and removing government documents. His primary defense was that his superiors, including President Reagan, authorized him to take the alleged actions and that such authorization negated any other proof or inferences of criminal intent.
North contends that the trial judge erred first by not instructing the jury as to a fully exculpatory “authorization defense,” and, second, by restricting the jury, in determining whether North had the requisite criminal intent, to considering evidence of authorization that showed (1)- North “was specifically ordered and directed by a superior to act contrary to the law,” (2) “no alternative was available to him to comply with the order by other lawful means,” and (3) “under the facts and circumstances [North] reasonably believed the order was legally proper.” J.A. 674-75. My colleagues correctly reject North’s first claim, but support North’s second claim with regard to Count 9 on the grounds that the district court committed error by preventing the jury from fully considering “whatever evidence of authorization exists in the record as it bears on the jury’s determination of whether North had subjective knowledge of unlawfulness.” Per Curiam at 885.
I believe the majority's reversal of Count 9 based on the judge’s failure to permit the jury to consider without limit any evidence of North’s superiors’ authorization of his illegal actions is without basis in the law. It permits a jury to excuse those “specific intent” crimes requiring knowledge of unlawfulness on the basis of a superior’s suggestion or broad directive, unaccompanied by any assurances of its legality.12 That result fatally undermines my colleagues’ own proper and correct conclusion that our criminal law does not recognize a “following orders” or “Nuremberg” defense. I therefore.dissent with respect to the reversal.of North’s conviction on Count 9.
A. North’s Purported “Authorization Defense”
We all agree that the trial judge did not err by failing to instruct the jury that authorization was a complete defense. See Per Curiam at 878-81. North argues alternatively, however, that he did not have the requisite criminal intent if he believed that his superiors authorized his illegal conduct and that the authorization was lawful. Brief of Appellant 37-38. Thus, he contends that he properly relied on the instructions of superior officers, who had apparent authority to order him to take certain actions.
Although North frames neither argument in terms of “justifications” or “excuses,” his basic claim resembles, but is actually much broader than, the limited excuse of reliance on an official misstatement of law, which our law does recognize. See Per Curiam at 881 n. 10. Defendants advancing an official misstatement defense must demonstrate that they (1) reasonably relied on (2) a misstatement of law provided by (3) a superior officially responsible for defining the relevant legal principles under which the actor must operate. This *927excuse, moreover, is an exculpatory affirmative defense, and requires that the defendant bear the burden of persuasion by establishing the defense through a preponderance of the evidence. See Model Penal Code (“MPC”) § 2.04(3), (4) (1985); Criminal Code Reform Act of 1977, S.Rep. No. 1437, 95th Cong., 1st Sess. 121-25 (1977); 2 P. Robinson, Criminal Law Defenses § 183 & n. 1 (1984) (listing state statutes incorporating this defense).
There are three critical differences between the official misstatement excuse and North’s claimed defense. First, the official misstatement excuse is available only to defendants who have been assured by their superiors that the actions in question are legal; the defendant is not exonerated merely by a supervisor’s directive to perform certain actions. Second, the supervisor must have the expertise and responsibility qualifying him to promise his subordinate that the actions he is authorizing are legal. Third, and perhaps most important, the defendant’s reliance on his superior’s authorization must be objectively reasonable. North does not accept any of these conditions as applying in his case.
In short, North’s proposed authorization defense strips away all of the restraints that prevent the reliance on an official misstatement excuse from turning into a mere following orders defense. But while purporting to reject his proffered authorization defense, my colleagues go on to insist that the jury should have been told that it could consider any evidence of purported authorization, without limitations, as it might bear on North’s specific intent in committing the criminal act of altering, destroying, or removing official records with the knowledge that his conduct was illegal. Indeed, they reverse North’s conviction on Count 9 because of the trial judge’s attempt to confine the jury’s consideration to the kind of authorization evidence recognized by the official misstatement of law doctrine. The perplexing result of their ruling is that a jury could acquit North for lack of intent on the basis of the very same evidence that they reject when raised in the guise of an authorization defense. Their formulation not only undermines established doctrines governing criminal intent but also frustrates the criminal law’s ability to restrain illegal conduct by government officials.
B. The Majority’s Improper Incorporation of Authorization Into the Determination of North’s Criminal Intent
The criminal law recognizes that some individuals who engage in illegal conduct are not genuinely “free agent[s] confronted with a choice between doing right and doing wrong and choosing freely to do wrong.” Morissette v. United States, 342 U.S. 246, 250 n. 4, 72 S.Ct. 240, 243 n. 4, 96 L.Ed. 288 (1952) (quoting R. Pound, Introduction, F. Sayre, Cases on Criminal Law (1927)). Consequently, without calling into question the communal morality it embodies, the criminal law recognizes the right of a defendant in certain limited circumstances to introduce certain kinds of evidence negating or overriding what would otherwise be assumed to be a specific intent to commit a crime. But rather than opening the door to any and all assertions of individual motives and morality, the law has established circumscribed justifications or excuses for what would otherwise be intentional crimes. Evolved over the centuries, these specific defenses provide a measured contrast to my colleagues’ reformulation of the jury’s deliberative role, which countenances no limits or control on the kinds of authorization evidence relevant to the specific intent of knowledge of unlawfulness.
In some cases, the actor himself may be unable to conform to governing principles of conduct. This may occur not only in cases of disability, such as insanity, intoxication, or immaturity, but also in cases of ignorance or mistake, concerning law or fact, or in a case of reliance on an official misstatement of law. Such situations may give rise to recognized excuses. See 1 P. Robinson, Criminal Law Defenses § 25(b).
Alternatively, external circumstances, limiting an actor’s choice to one between two legal wrongs, may prevent a person from acting lawfully, or justify otherwise *928unlawful conduct under certain extraordinary circumstances when society “encourage[s] or at least tolerate[s]” it. Id. § 25(d); see also Note, Justification: The Impact of the Model Penal Code on Statutory Reform, 75 Colum.L.Rev. 914, 916 (1975). Thus, a firefighter may be justified in setting fire to a field located between a raging inferno and an unsuspecting town in order to create a firebreak. A homeowner may be justified in assaulting a burglar. A policeman may be justified in breaking into a private house in order to execute a search warrant. See generally 1 P. Robinson, Criminal Law Defenses § 24(a). But such defenses are, in the main, limited to well-defined fact situations or to emergencies where in order to serve an uncontroverted and commonly-agreed upon higher good, a violation of law must be excused.
The majority’s rule allowing a jury to consider whatever evidence of authorization bears on North’s knowledge of the unlawfulness of his conduct would quickly outdistance and overtake the criminal law’s controlled evolution of narrow exceptions to a basic principle that the reasons why one intentionally violates the law are irrelevant. As described above, the reliance on an official misstatement excuse exculpates only those defendants whose illegal conduct was the result of a specific, official instruction accompanied by assurances that it was legal. The reliance on an official misstatement excuse represents society’s toleration point as to when its government servants may violate the law, even unwittingly. By contrast, the majority’s approach would allow any government official accused of a crime requiring knowledge of unlawfulness to plead any tacit or implicit approval of his superior as an excuse for violating his legal duties. This result would put our criminal law at the mercy of every corrupt government supervisor. If nothing else, the past two decades should have alerted us to the dangers of such a reworking of the law of intent. As a nation, we have experienced too often the havoc wreaked by zealous government personnel carrying out their personal— sometimes well-motivated, sometimes not— policy agendas with the acquiescence, authorization, or approval of equally zealous superiors in defiance of laws promulgated by our official lawmaking bodies.
In my view, therefore, Judge Gesell was not overrestrictive to North when he instructed the jury that it could “weigh ... authorization ... in determining [North’s] specific intent,” J.A. 674-75, only if the evidence met criteria bringing the authorization roughly within the boundaries of the official misstatement of law defense. He properly refused to allow an uncontrolled intrusion of evidence of putative authorizations into the jury’s consideration of North’s intent. Yet, my colleagues reverse North’s conviction on Count 9 on the grounds that the judge’s definition of what kind of authorization evidence could be considered under intent was too confining: they object to his requirements of (1) a specific directive, (2) the absence of another clearly legal means of complying with the directive, and (3) the defendant’s reasonable belief under the circumstances that the order was legal. In my view these restrictions were essential to prevent the dangerous potential of authorization evidence from escaping the bounds of the traditional official misstatement of law excuse.13
Thus, the issue on which my colleagues and I diverge is whether the trial judge’s strictures on the kind of authorization evidence the jury could consider prevented the jury from considering testimony legitimately relevant to North’s intent to alter, destroy, and conceal documents in knowing violation of the law. I believe the answer is “No,” and that the record in this case bears out my conclusion. If we compare the standard of criminal intent in the statute underlying North’s conviction on Count 9 with the authorization evidence he actual*929ly submitted at trial, the lack of any prejudicial effect on North from the judge’s instructions becomes clear.
C. Appropriateness of Limitations Placed by Judge Gesell on Authorization Evidence
1. Requisite Degree of Intent — 18 U.S.C. § 2071(b)
18 U.S.C. § 2071(b) prescribes a fine or imprisonment for a person, having custody of an official document, who “willfully and unlawfully conceals, removes, mutilates, obliterates, falsifies, or destroys the same.” 18 U.S.C. § 2071(b) does not require a “bad purpose,” and the “willfulness” criterion “is satisfied if the accused acted intentionally, with knowledge that he was breaching the statute.” United States v. Moylan, 417 F.2d 1002, 1004 (4th Cir.1969), cert. denied, 397 U.S. 910, 90 S.Ct. 908, 25 L.Ed.2d 91 (1970) (discussing “willfulness” criterion of companion 18 U.S.C. § 2071(a)). Even a highly “moral” purpose does not dilute the criminal intent of a person who intentionally destroys or alters an official document with the knowledge that he is breaking the law. Id. For conviction under 18 U.S.C. § 2071(b), then, it is sufficient that the government prove (1) that a defendant intends to deprive the government of the use of its records, see United States v. Rosner, 352 F.Supp. 915, 921 (S.D.N.Y.1972), and (2) that the defendant knows that his actions are unlawful or— what is in effect the same thing — lacks a reasonable belief that his actions are not unlawful, see generally Perkins, Ignorance and Mistake in Criminal Law, 88 U.Pa.L. Rev. 35, 49 (1939) (generally discussing “willful” intent).14
2. Application of Intent Requirements to Facts — 18 U.S.C. § 2071(b) (Count 9)
North testified that he did not consider any of the activities charged in Count 9 unlawful because of his superiors’ authorization. That purported authorization related to three specific criminal acts with which North was charged: Casey’s instruction to destroy the Contra operating fund ledger, Tr. 7138-39, and to “start cleaning ... up” other documents relating to the Iran initiative and the Iran-Contra connection, Tr. 7553; McFarlane’s instruction to “fix” the NSC System IY documents, Tr. 6903-07; and Secord’s counsel’s advice to remove documents from the NSC, Tr. 7109-13.
a. Specific Instruction
The trial judge told the jury that it could consider only evidence of a “clear, direct instruction[ ] to act at a given time in a given way.” J.A. 675. The instruction had to be “sufficiently precise to assure a reasonable person that it was intended to apply in the given circumstances that develop subsequently which were not otherwise stated.” Id. I cannot conclude, as my colleagues do, that this instruction unfairly prevented the jury from considering relevant evidence that bore on North’s knowledge that he was breaking the law by altering, destroying, and concealing official documents.
The only kinds of authorizations that the criminal law recognizes in any context as exculpatory are official misstatements of law that, by definition, are specific enough for the “authorizee” to apply them confidently in the relevant circumstances. See MPC § 2.04(3) comment 3, at 278 (official misstatement defense contemplates reliance on official misstatement contained in statute, judicial decision, administrative order, or other official interpretation of law). Allowing the jury to exculpate North on the grounds of authorizations that were not, in its view, even intended to control his conduct, but were mere suggestions or vague permissions to commit illegal acts if *930he felt like performing them goes beyond the pale of any interpretation of intent with which I am familiar. It lifts from any official below the President even the most minimal burden of finding out what the law is and what authority his superior has to countenance its violation. It literally invites an “aura of lawlessness” where officials infer that they need not obey the law, even when they are not under actual instructions to disobey it. If the jury interpreted North’s evidence of authorizations as only vague suggestions to “clean up” or “fix” key documents, then that evidence could not have had any legitimate effect on North’s knowledge that he was breaking the law by altering and destroying official documents. If the jury interpreted them— as North did — as orders to do these acts, then Judge Gesell’s specificity limitation would have been met.15 Either way, North was not prejudiced.
b. No Alternative Means of Compliance
Judge Gesell also told the jury to consider evidence of authorization only “if no alternative was available to [North] to comply with the order by other lawful means_” J.A. 674. The judge added that if “an authorization can be satisfied by two different courses of action, one clearly legal and one of dubious legality, and.a person chooses the illegal or dubious course when other, legal action would comply,” the jury could not consider the authorization evidence. J.A. 675. This instruction, of course, assumes that the jury has found that he was under specific orders in the first place. If that is the case, to comply North had to destroy, alter, and remove the documents. There were no alternative lawful means that could have accomplished that end; certainly none was brought up at trial. This aspect of Judge Gesell’s instruction, then, was incidental to the first condition and, by its nature, could not have independently excluded any evidence of purported authorization submitted by North.16
c. Reasonable Belief in the Legal Propriety of the Order
The judge’s instructions allowed the jury to consider evidence of a specific directive “provided under the facts and circumstances [North] reasonably believed the order was legally proper.” J.A. 675. North testified that he did believe his actions were legally proper. He stated that he “had always regarded as [his] personal files” the documents in his office that he destroyed pursuant to Casey’s request. Tr. 7560. Moreover, “[i]t never occurred to” North that altering the documents pursuant to McFarlane’s instructions was unlawful because “I had written those documents. I had prepared them for him. They were his documents.” Tr. 6907. North also testified that he believed that removing the documents was legal because Secord’s counsel was “at that point the only legal advice that I had.” Tr. 7110.
Judge Gesell’s instructions were, as a matter of law, correct in precluding the jury from considering evidence of authorization on which North relied unreasonably. Acknowledgedly, some courts have dis*931puted the legitimacy of a reasonableness requirement in showing lack of specific intent. Compare United States v. Rhone, 864 F.2d 832, 835 (D.C.Cir.1989) (even unreasonable mistakes of law exculpatory) with United States v. Aguilar, 883 F.2d 662, 674-75 nn. 4 & 5 (9th Cir.1989) (criticizing Rhone); Note, Ignorance of the Law as an Excuse, 86 Colum.L.Rev. 1392, 1416 n. 123 (1986) (pointing out that without reasonableness requirement, exculpation results from the most “bizarre and incredible mistakes of law”).17 But the consensus is overwhelming that a defendant’s mistake of law must be reasonable to be exculpatory. See Aguilar, 883 F.2d at 675 n. 5; United States v. Kelley, 539 F.2d 1199, 1204 n. 9 (9th Cir.), cert. denied, 429 U.S. 963, 97 S.Ct. 393, 50 L.Ed.2d 332 (1976); United States v. Barker, 514 F.2d 208, 235 n. 39 (D.C.Cir.) (Bazelon, C.J., concurring), cert. denied, 421 U.S. 1013, 95 S.Ct. 2420, 44 L.Ed.2d 682 (1975); Note, Ignorance of the Law, 86 Colum.L.Rev. at 1414-16; 2 P. Robinson, Criminal Law Defenses § 181(b)(2) (all arguing that preferable rule is to find mistakes of law exculpatory only when they are reasonable). This reasonableness requirement for mistakes of law should also be applied in the context of statutes requiring knowledge of unlawfulness for conviction, and at least one court has already done so. Aguilar, 883 F.2d at 671 n. 2 (statute at issue allowed for conviction of defendant “knowing that he is in the United States in violation of law”).18 To instruct that unreasonable reliance on a superior’s authorization for an illegal act (i.e., the superior was known to be incompetent or venal) can negate knowledge of unlawfulness introduces a novel and mischievous element into our criminal law.19
As for the part of the challenged instruction that required North to believe in the legality of his own actions, that seems an uncontrovertedly necessary component of any kind of evidence going toward intent. I cannot fathom on what basis the majority objects to it. Actually, no evidence at all was presented at trial that any of North’s putative “authorizers” ever told him that destroying, altering, or concealing documents was legal, and North himself apparently failed to take even the most minimal steps to determine what the law required.20 Nonetheless, evidence that he believed orders to destroy or alter documents were legal — as he testified — could be freely considered by the jury under the judge’s instruction, so long as his reliance was reasonable. On the other hand, to have permitted the jury to acquit North if he unreasonably believed that his superiors’ instructions were lawful or if he did not *932believe that they were lawful at all would make hash out of our criminal law. It would have been tantamount to an outright endorsement of the “following orders” defense from which my colleagues rightfully recoil.21
In sum, then, Judge Gesell’s limitations on the jury’s consideration of authorization evidence under Count 9 were entirely consistent with appropriate law interpreting 18 U.S.C. § 2071(b) and with the actual evidence proffered. North suffered no cognizable harm from them.
D. Conclusion
Simply following orders cannot transform illegal acts into legal ones. See Per Curiam at 880. My colleagues nonetheless insist that a jury be allowed to consider any and all varieties of authorization as exculpatory evidence showing lack of knowledge of unlawfulness. See id. at 885-86. This open-ended invitation for juries to exonerate defendants who simply follow orders runs counter to a most fundamental tradition of our criminal law, which is based on the notion that citizens, big and small, insider and outsider, have some independent responsibility to find out and conform to what the law requires of them. The trial judge’s authorization instructions here were more than generous to North's right to demonstrate his lack of knowledge of unlawfulness and there was nothing in his charge that remotely prejudiced North in such a way as to constitute reversible error. I dissent from the reversal of Count 9.
IV. Conclusion
I would affirm North’s convictions on all three Counts. I am satisfied that he received a fair trial before a jury of his peers and that no reversible error was committed.
. The majority contends that I ignore Rinaldi's "primary teaching ... that the government always bears the burden of proof and that we may not infer findings favorable to the government.” Per Curiam Opinion ("Per Curiam”) at 867 (emphasis in original). Not so. The crucial point is that once the government has demonstrated that a witness’ testimony is "free from taint and independently derived,” Rinaldi, 808 F.2d at 1583, Kastigar and Rinaldi impose no constraint on the prosecution’s use of that witness' testimony. They do not automatically preclude the prosecution’s use of evidence from witnesses exposed to immunized testimony.
. These last materials appear to constitute the "canned” evidence discussed at oral argument and in the Per Curiam at 871-872.
. My colleagues erroneously say that I concede that Judge Gesell "did not ... examine the grand jury transcripts for the presence of immunized testimony in the substance of witnesses' testimony.” Per Curiam at 867 (emphasis in original). This is not so. Although the judge identified some particular foci in his examination of the grand jury testimony, see Kastigar Memo, 698 F.Supp. at 308, the trial judge clearly performed that examination, id. at 315 (judge "relied on ... all testimony given” to grand jury in making Kastigar determination).
. My colleagues contend that a post-trial Kasti-gar hearing must encompass even witnesses "who happened to testify concerning matters not directly related to the conviction counts" because their testimony may have compromised North’s own credibility as a witness and may have influenced North’s decision to waive his right not to testify. Per Curiam at 868 n. 4. This view is quite astonishing in that it implies that the jury may have discredited North’s defense to conviction Counts on the basis of testimony that it necessarily discounted in acquitting North on other Counts. In light of North’s acquittal on nine of the twelve Counts of his • indictment, witnesses whose testimony was marginal or even entirely unrelated to Counts 6, 9, and 10 could hardly have had any effect on North’s credibility as to those Counts.
. I see absolutely no basis, therefore, for my colleagues’ concern that Judge Gesell’s apparent decision not to examine the additional "canned” materials may have prejudiced North. See Per Curiam at 871-72. With respect to the meeting critical to Count 6, Judge Gesell saw everything he needed to see in the IC’s submission of its independent “leads," which, to underscore my earlier point, contained summaries of the content of witnesses’ interviews with the FBI and, as a result, previewed their expected grand jury testimony.
.The majority is concerned that even assuming the consistency of the first witness’ testimony with his prior FBI interview, "we are still left with the other witness.” Per Curiam at 867. This apprehension is unwarranted. The testimony of the "other witness,” also present at the meeting critical to North's conviction on Count 6, was entirely duplicative of the testimony presented by the witness interviewed by the FBI; and at trial North himself confirmed both witnesses' accounts of his role at that meeting. See Tr. 7631. Thus, North clearly was not prejudiced by the lack of a Kastigar hearing concerning the “other witness."
. Interestingly, the majority employs the passive voice, concluding that ‘‘[a] central problem in this case is that many grand jury and trial witnesses were thoroughly soaked in North's immunized testimony...." Per Curiam at 863 (emphasis supplied). My criticism is not a stylistic one, however: The real "problem” in the case is that many of these witnesses, presumably aware of the ¡Castigar strictures under which the IC was operating, soaked themselves in the immunized testimony. In light of the substantial evidence relevant to the conviction Counts provided by witnesses to the grand jury and to the FBI before North’s immunized testimony, it goes beyond reason to insist that the IC must additionally demonstrate that Justice Department officials from the same Administration as North himself did not purposefully use North's immunized testimony in preparing for their own or their colleagues' grand jury appearances when their grand jury testimony added nothing of substance to their prior statements concerning the facts on which Counts 6, 9, and 10 of North’s indictment were based.
. Contrary to my colleagues’ characterization, I am not alleging any “conspiracy" among Administration officials. See Per Curiam at 865. I simply note the inordinate burden that is placed on the IC to counter witnesses’ intentional exposure to immunized testimony inflicted by government counsel themselves. The last portion — ignored by the majority, see id. at 865 —of my statement in note 7, supra, fully acknowledges that the critical test is whether North was prejudiced by such exposure. I believe the record shows that he was not.
. North’s counsel conceded at oral argument that North "did receive grand jury material with respect to witnesses at trial.” Oral Arg. Tr. 20.
. Contrary to my colleagues’ suggestion, the judge could not have determined that North’s post-trial claim presented "no new information” without comparing the trial and grand jury proceedings. See Per Curiam at 866. The judge’s finding was a substantive one, and there is no justification for the majority’s attempt to read less into the trial judge's words than they necessarily imply.
. In both Mangieri and United States v. Hubbard, 889 F.2d 277 (D.C.Cir.1989), we applied the "plain error" standard of review; this court has not yet confronted a case raising the issue of a particularized unanimity instruction in the "harmless error” context.
. My concern about the Per Curiam’s implications beyond the statute at issue is not "wholly irrelevant,” and I am well aware that Count 9 does not involve a "generic 'specific intent' requirement," whatever that means. See Per Cu-riam at 884 n. 13. First of all, while knowledge of unlawfulness is not a common specific intent standard, it is certainly not unique, see Babb v. United States, 252 F.2d 702, 707 (5th Cir.1958) (discussing "knowingly and willfully” requirement of 1'8 U.S.C. § 545), and in any event, the principles developed in the context of this case may well be applied to lower intent thresholds. See Dissent of Silberman, J., at 937-46 (linking finding of error on Count 9 instructions to alleged error on Count 6 instructions).
. I believe that many of the same arguments apply even in the case of "specific intent” statutes that do not require knowledge of unlawfulness for criminal intent. Nevertheless, despite my general concerns about the relationship between authorization and specific intent, I agree fully with the Per Curiam's narrower argument that evidence of authorization did not bear on whether North had the "corrupt” intent required by 18 U.S.C. § 1505.
. Absent a defendant’s admission that he knew his actions were unlawful, the government will ordinarily be able to show only that the defendant's belief that his actions were not unlawful lacked any reasonable basis. Judge Gesell instructed as much, charging the jury not only that "the defendant must have known his conduct was unlawful,” J.A. 649, but also that the jury could acquit for authorization only if North "reasonably believed the order was legally proper,” J.A. 675. See infra Part C(2)(c). Cf. Per Curiam at 885-886.
. My colleagues' implication that the jury was not supposed to "interpret” the putative authorizations, see Per Curiam at 887 n. 19, makes no sense. Presented with evidence of supposed authorizations, the jury had to decide whether the authorizations met the trial judge’s threshold conditions of specificity. How the jury was supposed to undertake that task without some cogitation and interpretation escapes me.
. The Per Curiam argues that this aspect of the trial judge's instructions was prejudicial because "these instructions require the jury to determine whether a course of action is legal, illegal, or of dubious legality ... without considering the evidence of authorization.” Per Curiam at 888 (emphasis in original). I believe my colleagues have misunderstood the trial judge's charge. As I read it, the point of the instruction is that the jury should not absolve North on the basis of an order to commit an otherwise illegal act if North could have achieved the same result in a clearly legal way. In considering whether a separate legal alternative was available, the jury would have no need to consider any authorization, since authorization comes into play only when a course of action is otherwise illegal. Thus, I do not credit the circularity that my colleagues fear, although for other reasons I find the instruction largely meaningless. See text accompanying, supra.
. While my colleagues find my concern about exculpation resulting from "bizarre and incredible mistakes of law” to be "exaggerated,” Per Curiam at 886, they themselves cite the case of Aitken v. United States, 755 F.2d 188 (1st Cir.1986), see Per Curiam at 886, in which the First Circuit found that the trial judge erred in failing to allow the jury to consider the claim of a defendant accused of "willful” failure to pay income taxes that he did not believe his wages constituted income because they constituted an exchange of time for money, with no gain for him. In my view, as well as others’, see Note, 86 Colum.L.Rev. at 1416 n. 123, that mistake of law was "bizarre and incredible.”
. Neither Judge Gesell’s reasonableness requirement — nor, for that matter, his other limitations — precluded the jury from considering North’s claim that the advice of Secord’s counsel to remove official documents after he was fired from the NSC led him to believe that the removal was lawful.
. My colleagues are concerned that Judge Ge-sell's requirement that North had to have a reasonable belief that his authorizers’ orders were legal is inconsistent with the "indispu-tablfe]” conclusion that 18 U.S.C. § 2071(b) "requires subjective knowledge of unlawfulness for conviction.” Per Curiam at 886 (emphasis in original). As explained in the accompanying text, I do not believe that even in the case of statutes such as 18 U.S.C. § 2071(b), the criminal law requires a jury to acquit a defendant whose claim that he lacked knowledge of unlawfulness is unreasonable. Indeed, without a reasonableness requirement like the judge’s here, simply following orders that a defendant considered lawful just because they were “orders” — no matter how unreasonable — would excuse a defendant from responsibility for what would otherwise be a knowing violation of the law — a result my colleagues claim to find as distasteful as I do.
.Of course, Judge Gesell’s strictures on authorization evidence did not affect the jury’s consideration of- North’s testimony that he independently presupposed the legality of his conduct.
. Judge Gesell’s "reasonableness” limitation did not make it “unreasonable as a matter of law to believe that one’s superiors in the NSC ... could authorize the destruction of internal NSC documents_’’ Per Curiam at 887 (emphasis in original). Under the instruction, the jury clearly had the option of deciding whether North’s reliance on the purported authorizations was reasonable or not, and — not surprisingly, in light of the absence of any evidence that North was told his conduct was lawful — they decided that his reliance was not reasonable. Nothing in Judge Gesell's instruction prevented the jury from "crediting] North’s claim that he did not think he was acting unlawfully,” Per Curiam at 887; insofar as that claim was based on purported authorizations, the instructions merely required the jury to find the claim reasonable in order to be exculpatory. North points to no record evidence of authorization that was excluded by the judge’s instructions (indeed, he argues "there was evidence of specific authorization,” North Reply Br. 9 (emphasis in original)) and the majority fails to identify what, if any, “evidence of authorization in the record ... was excluded by the district court’s instructions.” Per Curiam at 887.