GARWOOD, Circuit Judge:
Defendants-appellants Douglas Williams (Williams), Buford “Red” Salter (Salter), Ronald May (May), Buddy LeDoux (Le-Doux), Kenneth Tyler (Tyler), Larry Wiggins (Wiggins), and Dugan Phillips (Phillips) appeal from their convictions for obstruction of justice under 18 U.S.C. § 1503. The jury found Williams guilty of corruptly, and with the intent of impeding the due administration of justice, endeavoring to influence a subpoenaed grand jury witness to give false testimony. The remaining appellants were convicted under section 1503 for endeavoring to obstruct the due administration of justice by giving specified false testimony before a grand jury in a manner that blocked the flow of truthful information and impeded justice. All of the appellants received probated confine[970]*970ment sentences and were assessed fines ranging from $2,500 to $10,000.1
Counsel for Douglas Williams has filed a Suggestion of Death advising that Williams died on or about May 6, 1989, after submission of this appeal on oral argument but while decision was still pending. We accordingly hereby sever Williams’ case from that of all the other appellants and remand Williams’ case to the district court with instructions to vacate his judgment of conviction and sentence and to dismiss the indictment as to him because of his death. See United States v. Welborn, 849 F.2d 980, 985 (5th Cir.1988); United States v. Pauline, 625 F.2d 684, 685 (5th Cir.1980).
The remaining appellants (hereafter collectively “appellants”) claim that their convictions should be overturned because (1) there was prosecutorial abuse of the grand jury process; and in any event, (2) there was insufficient evidence to support their convictions since it was not shown that their grand jury testimony had the effect of impeding justice or entirely closing off avenues of the grand jury’s inquiry. We find that the prosecutor did not abuse the grand jury process in a manner that justifies overturning these appellants’ convictions, and that there was sufficient evidence to support their convictions. We accordingly affirm as to them.
Facts and Proceedings Below
Appellants’ convictions are the remaining vestiges of a forty-seven-count indictment against members of the Fredeman family, their companies, and employees for alleged violations of the Racketeer Influenced and Corrupt Organizations Act (RICO), 18 U.S. C. § 1961 et seq., and related offenses, primarily in relation to the Fredeman companies’ “midstream” fueling operations.2 The Fredemans, of Port Arthur, Texas, own and operate several companies that engage in the towing and fueling of vessels in the coastal waters of East Texas, Louisiana, and to some extent, Mississippi and Alabama.3
The Fredeman business began in the 1940s when William “Cap” Fredeman, Sr. converted a shrimp boat to a towboat and began Port Arthur Towing Company (PAT-CO). The company prospered in the post-World War II boom, and in 1957 Cap Frede-man opened one of the first “midstream” fueling operations, Channel Marine Fueling Service. In 1968, the Fredemans established another midstream fueling company, Palmer Midstream.4 The Fredemans rapidly became the dominant presence in the area’s marine fueling industry.5
Refueling a customer vessel generally involved attaching a hose from a Fredeman [971]*971supply vessel to the fuel hatch of the customer vessel. A meter on the Fredeman vessel recorded the fuel dispensed; however, many of the customers’ vessels did not have devices to accurately record the fuel they received. Allegedly in about ninety percent of their fueling transactions the JVedemans underdelivered fuel to their customers’ vessels.
Basically two methods of cheating were employed. The “hit” valve method involved diverting fuel back to the Fredeman supply vessel through a concealed hose that ran under the supply vessel’s deck and back into its supply tank. The other method involved running up the meter before attaching the hose to the customer’s fuel hatch. Several former Fredeman employees testified, before the grand jury and at trial, that the company goal was to steal ten to fifteen percent of the customer’s “purchased” fuel.6
The appellants were all long-time employees of the Fredeman companies.7. Each of them, at various times throughout their employment, was in a position to observe and participate in the fuel thefts. Some of the appellants were in a position to direct other employees to steal fuel and to instruct employees in the methods of stealing fuel. Salter was a dock manager in Louisiana, Mississippi, and Alabama. Le-Doux had worked as a deckhand, mate, boat captain, and also as a dock manager in Louisiana before he assumed an office position. May was a boat captain and later a dock manager. Tyler was a deckhand, boat captain, and later a dock manager. Wiggins was a deckhand, tankerman, and boat captain. Phillips was a deckhand, boat captain, and later a dock manager.8
While the Fredemans’ profits grew, many of their competitors’ profits withered.9 In 1983, one of the Fredemans’ primary competitors filed a federal antitrust suit against the Fredemans charging the Fredemans with monopolization of fuel sales by theft, bribes, and fraud.10 In this civil suit, all of the appellants were deposed in 1983 and each denied any knowledge of such activity within the Fredeman organization. Early in 1984, the district court that was presiding over the civil suit referred the allegations of wrongdoing to a federal grand jury for investigation.11
The grand jury investigation continued through 1985 and into 1986. On October 2, 1985, Stephen Landry, a former Channel Fueling employee, testified that fuel thefts had occurred. This was in direct contradiction to his earlier deposition testimony in the civil suit where he had denied knowledge of any thefts.
LeDoux, Salter, May, Wiggins, Tyler, and Phillips testified before the grand jury in January and February 1986.12 They each denied any knowledge of the inten[972]*972tional fuel underdeliveries or thefts — a position that was consistent with their civil suit depositions testimony. Prior to giving their grand jury testimony, the prosecutor at the grand jury proceedings told each appellant that he was not currently a target of the investigation. The prosecutor advised each appellant that he was subpoenaed as a witness to provide any information that he possessed with regard to the general investigation into the fuel underde-liveries.13 The appellants were also cautioned that they could be charged with perjury for each false statement they made under oath. In addition, the prosecutor told the appellants that they had the right to consult their attorney at any time during the questioning,14 and the majority of the appellants were advised in the presence of the grand jury of their Fifth Amendment rights.15
On April 17, 1986, the federal grand jury returned a forty-seven-count indictment charging the Fredemans, the Fredeman Companies, and several Fredeman employees with violations of RICO and related statutes. The appellants were charged with RICO conspiracy and substantive RICO violations. In addition, the appellants were charged with obstruction of justice in violation of 18 U.S.C. § 1503 by “knowingly, intentionally and corruptly endeavor[ing] to obstruct the due administration of justice by testifying falsely under oath to the Grand Jury, in a manner that blocked the flow of truthful information” and “impeded justice.”
After four months of trial, eighteen counts were submitted to the jury for deliberation. The jury found each of the appellants guilty of one count of obstructing justice under 18 U.S.C. § 1503. The jury acquitted all appellants on two counts16 and was unable to reach a verdict on the remaining counts. The appellants were later sentenced, and they timely bring this appeal.
Discussion
Appellants claim that there was prosecu-torial abuse of the grand jury process that requires reversal of their convictions under the due process clause of the Fifth Amendment or in the exercise of our supervisory power. They also assert there was insufficient evidence to support their convictions because, they contend, it is not shown that their grand jury testimony had the effect of impeding justice or entirely closing off avenues of the grand jury’s inquiry.
I. Abuse of the Grand Jury Process
Appellants assert that the charges against them for obstruction of justice under 18 U.S.C. § 1503 were “manufactured” by the prosecution. They claim that the prosecutor, believing that he could prove that they had lied in their civil depositions, [973]*973induced them to commit perjury before the grand jury by telling them they were not targets of the grand jury investigation. Allegedly, the prosecutor induced the perjury in order to create obstruction of justice counts that would bolster the government’s RICO case.17
Appellants state that the record demonstrates that the sole reason that appellants were subpoenaed before the grand jury was to trap them into committing perjury.18 The district court did note that the prosecutor engaged in some questionable practices. In particular, it questioned the prosecutor’s practice of advising appellants that they were not targets of the investigation when the prosecutor believed he could prove they had lied in their earlier depositions.19 However, the use of improper prosecutorial tactics does not automatically lead to the conclusion that the prosecutor’s primary or sole intent in bringing appellants before the grand jury was to manufacture charges rather than to investigate crime.
It is undisputed that all of the appellants were employees of the Fredeman companies and that they all had firsthand knowledge of the Fredemans’ midstream fueling operations. Several of the appellants had worked for the Fredemans for over twenty years and, thus, unlike many of the former short-term employees who testified for the government, they possessed an immense storehouse of information.20 Appellants’ [974]*974testimony was clearly relevant, and potentially significant to the grand jury investigation. In addition, the grand jury has the right to observe a witness’ spontaneous responses, rather than contenting itself with the witness’ prior civil deposition involving similar questions. See, e.g., United States v. Vesich, 724 F.2d 451, 461 (5th Cir.1984), reh’g denied, 726 F.2d 168 (1984).
The prosecutor’s knowledge that the appellants had lied in their civil depositions does not lead to a presumption that the appellants would falsely testify before the grand jury. Id. It is more than a wholly abstract or theoretical possibility, even without a grant of immunity, that a witness who has previously lied in a civil suit will decide to tell the truth before a federal grand jury. Indeed, in the present case, at least one trial witness who had lied previously decided to testify truthfully because federal investigators became involved in the matter.21
The prosecutor clearly and emphatically informed each of the appellants of the possibility of a perjury charge for telling falsehoods under oath. In some instances, the prosecutor interrupted his line of questioning to remind an appellant of the possibility of a perjury charge for false statements under oath.22 These emphatic and sometimes repeated warnings regarding the possibility of perjury charges are inconsistent with a singular motive to induce perjury in order to create obstruction of justice charges.
Despite the appellants’ long-term, intimate knowledge of the Fredemans’ fueling operations, and the prosecutor’s clear warnings regarding penury, appellants claim that the prosecutor’s sole motive in subpoenaing them was to “induce” them to commit perjury through misrepresentation of their target status. We reject this contention.
The present case substantially differs from Brown v. United States, 245 F.2d 549 (8th Cir.1957), relied on by appellants, where the Court reversed a conviction for perjury before a Nebraska grand jury. The ultimate ground of decision there seems to have been that the evidence was not sufficient to show that any falsity in the testimony was “willful and corrupt” or anything more than the product of “ ‘lifting a statement ... out of ... context’ ” and then distorting its meaning. The opinion concludes by reversing “for insufficiency of the evidence.” Id. at 556. However, it is likewise evident that this result was influenced by the Court’s concern that the only purpose of calling the defendant before the Nebraska grand jury was to indict him for perjury before that body, as the underlying conduct concerning which he was questioned all occurred in Missouri, and whatever the defendant might have said could have “had no tendency to support any possible action of the [Nebraska] grand jury within its competency.” Id. at 555. This is simply not the present situation. Here, there were objectively valid reasons for the prosecutor to call appellants before the grand jury — given their employment history, their truthful testimony could well have advanced the grand jury’s actual and wholly legitimate investigation into the fuel theft conspiracy, particularly as to those in higher positions within the Fredeman companies. As has been frequently observed, “ ‘[a] grand jury investigation is not fully carried out until every [975]*975available clue has been run down and all witnesses examined’ ” and “[ljeads to further inquiry may be of material worth to [such] an investigation.’ ” See Vesich, 724 F.2d at 460, 461 and authorities therein. Just because appellants had denied knowledge in their 1983 depositions in the private civil suit, and the prosecutor thought he could prove those denials were false, does not require the prosecutor to assume that appellants would testify untruthfully before the grand jury in 1986. Id. Certainly the prosecutor could not know that they would so testify; and if they did not, their testimony would likely have been relevant and helpful to the investigation. Even if the prosecutor in 1986 thought it more likely than not that they would repeat their previous 1983 denials — which has not been clearly established here — in this setting that would not suffice. Other federal appellate courts have not extended Brown to such a situation. See United States v. Chevoor, 526 F.2d 178, 185 (1st Cir.1975), cert. denied, 425 U.S. 935, 96 S.Ct. 1665, 48 L.Ed.2d 176 (1976); United States v. Nickels, 502 F.2d 1173, 1176 (7th Cir.1974), cert. denied, 426 U.S. 911, 96 S.Ct. 2237, 48 L.Ed.2d 837 (1976); United States v. DiGiovanni, 397 F.2d 409, 412 (7th Cir.), cert. denied, 393 U.S. 924, 89 S.Ct. 256, 21 L.Ed.2d 260 (1968).
Nor does a different result obtain because appellants were allegedly falsely advised that they were not “targets” of the grand jury investigation. It is settled that a “target” defendant is not constitutionally entitled to advice of his target status, or even of his Fifth Amendment rights, when called to testify before the grand jury. See United States v. Wong, 431 U.S. 174, 97 S.Ct. 1823, 1825-26, 52 L.Ed.2d 231 (1977); United States v. Washington, 431 U.S. 181, 97 S.Ct. 1814, 1819, 52 L.Ed.2d 238 (1977); United States v. Valentine, 820 F.2d 565, 572 (2d Cir.1987); United States v. Babb, 807 F.2d 272, 276-78 (1st Cir.1986); United States v. Weiss, 752 F.2d 777, 785-86 (2d Cir.1985); United States v. Scrimgeour, 636 F.2d 1019, 1026 (5th Cir.1981); United States v. Crocker, 568 F.2d 1049, 1053-56 (3d Cir.1977). The above principles have been applied even as to affirmative mis advice concerning nontarget status. Babb; Weiss; Crocker. In Scrimge-our, we relied on Crocker and approvingly described its holding as follows: “In Crocker, the Government misled the defendant by telling him that he was not a target of the investigation, yet the perjury indictment was held to be valid despite a due process challenge.” Scrimgeour, 636 F.2d at 1026 (emphasis in original).
Here appellants were apparently all warned of their Fifth Amendment rights, were told that although they were not presently “targets” they might yet be indicted, and were specifically warned that they could be charged with perjury for each false statement made to the grand jury. They were very familiar with the nature of the grand jury’s investigation. They had counsel available at the time of their testimony, and the prosecutor told them that they could interrupt the questioning to consult their attorneys, should they desire to do so. Under these circumstances, we are not only unable to find a constitutional infirmity in appellants’ convictions but we deem it inappropriate to set them aside on the basis of our supervisory power. We note in this connection that the principal vice of misinforming the witness that he is not a target is that he may be misled into waiving his Fifth Amendment rights — he may incriminate himself, or provide leads to the discovery of evidence against him, because he thinks he will not in any event be charged. See Babb at 277-79. However, “ ‘[t]he privilege against self-incrimination bars compelled testimony as to past crimes; it does not shelter new perjury’ ” and “ '[o]ur legal system provides methods for challenging the Government’s right to ask questions — lying is not one of them.’ ” Id. at 277. We have before us only appellants’ convictions for their false testimony before the grand jury. Advice or misad-vice as to nontarget status is certainly no more calculated to produce false testimony under oath — especially when perjury is warned against — than it is to produce honest answers. While we strongly disapprove of any prosecutorial misleading of a grand jury witness, it likewise would ill [976]*976serve the administration of justice to suggest that a judicially cognizable nexus may exist between a grand jury witness’ belief that he personally is not a target of the investigation and his decision to thereafter give false testimony under oath to the grand jury. This is especially so here, given the express warnings of perjury, the witnesses’ knowledge of what was being investigated, and the availability to them of their counsel.23
We reject the contentions of appellants that their convictions under section 1503 for giving false testimony to the grand jury should be reversed because of alleged pros-ecutorial abuse of the grand jury process.
We turn now to appellants’ claims of insufficiency of the evidence.
II. Obstruction of Justice
Appellants were all convicted on one count each of obstruction of justice in violation of 18 U.S.C. § 1503. Section 1503 provides in pertinent part:
“Whoever corruptly, or by threats or force, or by any threatening letter or communication, endeavors to influence, intimidate, or impede any grand or petit juror, or officer in or of any court of the United States, ... in the discharge of his duty, or injures any such grand or petit juror in his person or property on account of any verdict or indictment assented to by him, or on account of his being or having been such juror, or injures any such officer, ... in his person or property on account of the performance of his official duties, or corruptly or by threats or force, or by any threatening letter or communication, influences, obstructs, or impedes, or endeavors to influence, obstruct, or impede, the due administration of justice, shall be fined not more than $5,000 or imprisoned not more than five years, or both.” 18 U.S.C. § 1503 (emphasis added).
Section 1503 was enacted to protect individuals involved in federal judicial proceedings and to prevent “miscarriage[s] of justice by corrupt methods.” Vesich, 724 F.2d at 453 (quoting Samples v. United States, 121 F.2d 263, 265 (5th Cir.), cert. denied, 314 U.S. 662, 62 S.Ct. 129, 86 L.Ed. 530 (1941)). The omnibus clause, emphasized above, clearly forbids all corrupt endeavors to obstruct or impede the due administration of justice.24 See, e.g., United States v. Rash-[977]*977eed, 663 F.2d 843, 852 (9th Cir.1981), cert. denied, 454 U.S. 1157, 102 S.Ct. 1031, 71 L.Ed.2d 315 (1982); United States v. Griffin, 589 F.2d 200, 206 (5th Cir.), cert. denied, 444 U.S. 825, 100 S.Ct. 48, 62 L.Ed.2d 32 (1979). There are three core elements that the government must establish to prove a violation of the omnibus clause of section 1503: (1) there must be a pending judicial proceeding; (2) the defendant must have knowledge or notice of the pending proceeding; and (3) the defendant must have acted corruptly with the specific intent to obstruct or impede the proceeding in its due administration of justice. See, e.g., Rasheed, 663 F.2d at 851—52; United States v. Partin, 552 F.2d 621, 641-42 (5th Cir.), cert. denied, 434 U.S. 903, 98 S.Ct. 298, 54 L.Ed.2d 189 (1977); see also Vesich, 724 F.2d at 454, 457.25
Appellants were charged with “knowingly, intentionally and corruptly endeav- or[ing] to obstruct the due administration of justice by testifying falsely under oath to the grand jury, in a manner that blocked the flow of truthful information” and “impeded justice,” in violation of 18 U.S.C. § 1503.26 They do not dispute that they had knowledge of the subject matter being investigated by the grand jury nor that each of them testified falsely before the grand jury with the specific intent to impede the due administration of justice. Rather, they urge that the government failed to plead and prove, as they assert is required by United States v. Griffin, 589 F.2d 200 (5th Cir.1979), that their false testimony had the actual effect of obstructing justice in that it closed off avenues of [978]*978inquiry entirely. The argument in this connection essentially rests on two propositions; first, that section 1503 only proscribes conduct which constitutes contempt of court; and, second, that perjury itself does not constitute contempt unless there is added to it the further element of obstruction to the court in the performance of its duty.
The contention as to the scope of section 1503 is essentially historical. Section 1503 derives from section 2 of the Act of March 2, 1831, 4 Stat. 487.27 The first section of the Act of March 2, 1831 has now become 18 U.S.C. § 401.28 As recounted in Nelles & King, Contempt by Publication in the United States, 28 Colum.L.Rev. 401; 28 Colum.L.Rev. 525 (1928), the Act of March 2, 1831 had its genesis in the impeachment trial of United States District Judge James Peck, who had held a lawyer in contempt for writing a newspaper article critical of a decision recently rendered by Judge Peck (the lawyer was counsel in several similar cases still pending before the judge). In January 1831, Judge Peck was acquitted in the Senate by the margin of but a single vote. Id. at 426-30. Shortly thereafter, the House instructed its Judiciary Committee “ ‘to inquire into the expediency of defining, by statute, all offences which may be punishable as contempts of the courts of the United States’ ”; such a bill was promptly introduced, was passed by the House on February 28, 1831, and ultimately became the Act of March 2, 1831. Id. at 430. It is important to note, however, that as originally passed by the House, the bill contained only the first section (what is now section 401), and the second section (what is now section 1503) was added by the Senate (and subsequently amended by the House). Id. at 530-31. Though there appears to be no express legislative history explaining the purpose or intended scope of the second section, Nelles and King infer that it was intended to fill the void presumably left by the limitations on the contempt power which the first section imposed. Id. at 531.
Appellants further rely on the decisions in Ex parte Hudgings, 249 U.S. 378, 39 S.Ct. 337, 63 L.Ed. 656 (1919), and In re Michael, 326 U.S. 224, 66 S.Ct. 78, 90 L.Ed. 30 (1945), holding that perjury alone, in trial (Hudgings) or before the grand jury {Michael), could not be punished summarily by the court as contempt, unless there were “added to the essential elements of perjury ... the further element of obstruction to the court in the performance of its duty.” Hudgings, 39 S.Ct. at 340; Michael, 66 S.Ct. at 80. The latter element [979]*979“must clearly be shown." Hudgings at 339; Michael at 80.
Putting these principles together, the Sixth Circuit in United States v. Essex, 407 F.2d 214 (6th Cir.1969), held that making and filing with the court a false affidavit in an unsuccessful effort to obtain a new trial cannot be prosecuted under section 1503. This same history and authority was unsuccessfully pressed on us in Griffin, where we responded by stating, inter alia, “we doubt that the limitation on a federal judge’s power to punish perjury summarily is also a limitation on the power to punish under § 1503,” id. 589 F.2d at 205, and “we see no reason ... to depart from the natural construction of the statute by reading the restrictive law of summary contempt into § 1503.” Id. at 206. We remain of that view.
In the first place, while it is doubtless a reasonable inference that the general motivation for the second section of the Act of March 2, 1831 was to fill the void which would be brought about by the first section, it does not necessarily follow that the second section did no more than that. Certainly there is nothing in the wording of the enactment which limits the second section to matters which would have constituted contempt absent the first section; nor are we aware of any legislative history reflecting such an intent.29 Indeed, it has been held that the second section is not limited to filling the void left by the first section, as the second section may be violated by conduct punishable as contempt under the first. See Ex parte Savin, 131 U.S. 267, 9 S.Ct. 699, 701, 33 L.Ed. 150 (1889); United States v. Harris, 558 F.2d 366, 368 (7th Cir.1977). Moreover, the overriding purpose of the Act of March 2, 1831 was plainly to ensure that “the category of criminal cases which could be tried without a jury was narrowly confined.” Nye v. United States, 313 U.S. 33, 61 S.Ct. 810, 815, 85 L.Ed. 1172 (1941). Nothing in that purpose supports an artificially limiting construction of the second section. In the second place, it may be doubted that the Hudgings-Michael limitations on peiju-ry as contempt were clearly established or understood in 1831. Hudgings, decided eighty-some years later, observes that “there are decided cases which treat perjury, without any other element, as adequate to sustain a punishment for contempt.” Id., 39 S.Ct. at 340. See also Clark v. United States, 289 U.S. 1, 53 S.Ct. 465, 468, 77 L.Ed. 993 (1933)30; Griffin, 589 F.2d at 205-06.31 Indeed, the holdings in Hudgings and Michael appear to be based in large part on the desirability of limiting the range of conduct prosecutable without the customary safeguards of indictment and trial by jury. Thus Michael states that broad contempt powers “would permit too great inroads on the procedural safeguards of the Bill of Eights, since contempts are summary in their nature, and leave determination of guilt to a judge rather than a jury” and, significantly, at once goes on to say: “It is in this Constitutional setting that we must resolve the issues here raised.” Id., 66 S.Ct. at 79-80.32 No such [980]*980concerns are or ever were implicated in construction of either the second section of the Act of March 2, 1831 or section 1503. Accordingly, it seems highly dubious to retroactively, so to speak, apply the holdings of Hudgings and Michael in order to ascertain the intended coverage of section 2 of the 1831 statute.
It is also argued that there was no need to have false testimony covered by section 2 of the Act of March 2, 1831 because such conduct was also covered by the general perjury statute. Act of April 30, 1790, sec. 18, 1 Stat. 116.33 The offenses do or did not completely overlap, however. Perjury requires that the testimony be given under oath (or affirmation), while there is no such requirement in section 1503 or its predecessor. On the other hand, section 1503 requires a specific intent to impede the administration of justice, United States v. McComb, 744 F.2d 555, 561 (7th Cir.1984); United States v. Johnson, 585 F.2d 119, 128 (5th Cir.1978); United States v. Moon, 718 F.2d 1210, 1236 (2d Cir.1983), while the mental state required for perjury is that the statement be made intentionally and with knowledge of its falsity. See United States v. Norris, 300 U.S. 564, 57 S.Ct. 535, 538-39, 81 L.Ed. 808 (1937); Bronston v. United States, 409 U.S. 352, 93 S.Ct. 595, 600, 34 L.Ed.2d 568 (1973) (“the state of mind of the witness is relevant only to the extent that it bears on whether ‘he does not believe [his answer] to be true’ ”). While these states of mind are quite similar, they are not identical. Further, the penalty for perjury included three years’ confinement when the 1831 statute was enacted, while under section 2 thereof the maximum confinement was three months,34 and perjury, the much more serious offense, was more difficult to establish, generally requiring proof of falsity by two witnesses.35
However, we did not determine in Griffin whether all knowingly false grand jury testimony ipso facto constitutes a violation of section 1503, although we intimated that it might, saying “had Griffin’s testimony been merely false, it might well have come under the terms of the omnibus clause of § 1503, nonetheless.” Id., 589 F.2d at 204. We did not reach that issue because we held that Griffin’s testimony was not only false but also “had the effect of impeding justice”, id., and that “his denials of knowledge had the effect of closing off venues of inquiry entirely.” Id. at 205. Appellants seize on this language in Griffin and interpret it as in effect requiring independent proof that the grand jury’s investigation was actually impeded in some way beyond merely being denied the evidence that could have been obtained from appellants had they not falsely denied all knowledge of the matters they were asked about, which were admittedly highly material to the investigation. We reject this construction of Griffin as being out of harmony with the overall thrust of our [981]*981opinion there. As recited in that opinion, Griffin’s grand jury testimony on which his section 1503 conviction rested consisted in significant part of the same sort of short, flat, and wholesale false denials of knowledge as those of our appellants here.36 It is true that some other aspects of Griffin’s testimony might more accurately be described as evasive or a mere denial of memory, rather than a flat, unequivocal denial of any knowledge.37 However, we refused to attach significance to that purported distinction:
“We find it impossible to differentiate a flat refusal to testify from an evasive answer or a falsehood such as Griffin’s. ... By falsely denying knowledge of events and individuals when questioned about them, Griffin hindered the grand jury’s attempts to gather evidence of loansharking activities as effectively as if he refused to answer the questions at all.” Id. at 204.38
The same is true of appellants: their false denials of knowledge of events when questioned about them hindered the grand jury’s attempts to gather evidence of the fuel shorting scheme as effectively as if they had refused to answer the questions at all. These denials of knowledge had the effect of closing off entirely the avenues of inquiry being pursued, namely, what appellants knew about the subject under investigation.
To require that the government specifically prove that appellants knew some particular, identifiable fact about the fuel thefts which was not discovered or discoverable by the grand jury from sources other than the appellants themselves is, it seems to us, inconsistent with section 1503 and our interpretation of it in Griffin. It is settled that an un successful “endeavor” to obstruct justice violates section 1503; justice need not actually have been obstructed. United States v. Russell, 255 U.S. 138, 41 S.Ct. 260, 261, 65 L.Ed. 553 (1921); Rasheed, 663 F.2d at 853. Section 1503 “makes an offense of any proscribed ‘endeavor,’ ” without regard to the technicalities of the law of attempts or the doctrine of “impossibility.” Osborn v. United States, 385 U.S. 323, 87 S.Ct. 429, 435, 17 L.Ed.2d 394 (1966) (emphasis added). This is equally applicable to endeavors to influence a witness. See, e.g., Falk v. United States, 370 F.2d 472, 475 (9th Cir.1966) (attempt to get two witnesses to give false alibi testimony at trial violates section 1503 although neither witness actually testified); United States v. Davis, 752 F.2d 963, 968, 973 & n. 11 (5th Cir.1985) (urging and advising a witness to testify falsely violates section 1503; when so solicited, the witness had already secretly agreed to cooperate with the government and the conversation was recorded); United States v. Tedesco, 635 F.2d 902, 904, 907 (1st Cir.1980); United States v. Silverman, 745 F.2d 1386, 1394 n. 11, 1395 (11th Cir.1984) (“the success of the attempt to influence a witness is not a necessary element of the offense” and “the prosecution need not prove that the due administration of justice was actually obstructed or impeded”). In Griffin, [982]*982we rejected what might have been an arguable construction of section 1503, namely, that it applied only to influencing or interfering with other witnesses or nontestimo-nial evidence. Id., 589 F.2d at 203-04. We refused to recognize for this purpose “a distinction between one who induces a witness to commit perjury ... and one who perjures himself,” stating:
[981]*981"Q. Do you know anyone named Angelo?
[982]*982“[Ujsing threats or bribes to prevent a grand jury witness from testifying truthfully has the result of concealing and altering the nature of evidence. If such conduct constitutes an obstruction of the administration of justice, as we held in Partin [United States v. Partin, 552 F.2d 621, 641 (5th Cir.), cert. denied, 434 U.S. 903, 98 S.Ct. 298, 54 L.Ed.2d 189 (1977)], then so does testifying falsely; the result in either case is the same.” Griffin, 589 F.2d at 203 (footnote omitted).
To suggest, then, that appellants’ false denials of any knowledge of the material matters they were asked about must have actually impeded the grand jury in some way beyond having the same effect as if appellants had wholly refused to testify, thus entirely closing off appellants’ observations and knowledge of the fuel thefts as avenues of grand jury inquiry, is to essentially either require more than an “endeav- or” or to restrict section 1503 in this respect to actions directed against other witnesses or nontestimonial evidence. Neither course is open to us.
There was ample evidence provided by the government that each appellant testified falsely before the grand jury with the specific purpose of impeding the grand jury’s investigation. There were numerous former employees of Fredeman’s who had worked with or under each of the appellants and who testified to appellants’ participation in the fuel thefts. Each of the latter had worked for the Fredemans for several years. Some of them had been hired by a Fredeman. The former employees who admitted that stealing occurred were often unable to give specifics on the Fredemans’ personal involvement in the scheme, perhaps because they were for the most part shorter-term employees who would not have been in a position to discuss or observe the Fredemans’ illegal activity. All of these appellants had intimate knowledge of all aspects of the fueling operation and were long-time employees who more than likely possessed incriminating knowledge as to the Fredemans themselves. Their persisted in, flat, total denials of any knowledge when questioned before the grand jury were not only false, but also were intended and calculated to impede the grand jury’s investigation as effectively as if they had refused to answer the questions at all and had the effect of closing off entirely the avenues of inquiry which appellants represented. There is no evidence to suggest that appellants’ united, false “stonewalling” before the grand jury had any other purpose or any lesser effect. We are bound by Griffin, and under any reasonable reading of it, this suffices to make out a section 1503 violation.
Conclusion
Because of Williams’ death, his appeal is severed from that of the other appellants, and Williams’ case is remanded to the district court with instructions to vacate his conviction and sentence and to dismiss the indictment as to him.
As to all the other appellants, their complaints on appeal present no reversible error, and their convictions and sentences are accordingly affirmed.
REMANDED with instructions as to Williams; otherwise AFFIRMED.