Plaintiff-appellant Salim Aoude rails against the involuntary dismissal of two suits which he filed against defendant-ap-pellee Mobil Oil Corporation and others. The record of the case amply illustrates that, though the “bread of deceit is sweet to a man ... afterwards his mouth shall be filled with gravel.” Proverbs 20:17. We told a part of the tawdry tale in
Aoude v. Mobil Oil Corp.,
I
The general scenario of plaintiff’s effort surreptitiously to acquire a Mobil franchise from another service station operator, John Monahan, and to force Mobil to accept the transaction, was recounted at some length in our earlier opinion. Id. at 891-92. Rather than revisit that narrative, we refer the interested reader to it, noting especially that, to gain bargaining leverage with Mobil, Aoude concocted, backdated, and persuaded Monahan to sign, a bogus purchase agreement. See id. at 891 & n. 2. The counterfeit reflected a price nearly twice what had actually been paid for Monahan’s interest. When Mobil refused to bow to this artificially induced pressure, Aoude brought suit in state court, alleging, on a number of theories, that he had become the owner of Monahan’s franchise, notwithstanding Mobil’s refusal — as was its right — to honor the purported assignment. The complaint sought equitable relief and damages.
*1117 Plaintiff had given the ersatz agreement to his then-counsel, and it formed the complaint’s centerpiece. Aoude knew that counsel had annexed the false agreement to the complaint instead of the real one; indeed, Aoude approved the filing of the suit on that basis. By his own admission, he “did not ask [his attorney] to amend the complaint” to retract the lie. Mobil, unaware that the agreement was a work of fiction, removed the case to federal district court based on diversity of citizenship and amount in controversy.
During the first four months of 1988, numerous depositions were conducted and other discovery undertaken. Aoude participated fully, plying Mobil with interrogatories and requests for document production and responding to Mobil’s discovery initiatives. When Monahan’s deposition was taken, the truth began to emerge. Later, during his own deposition, Aoude was confronted with Monahan’s testimony and only then admitted the scheme. It was not until May 26, 1988 (almost three months after his deposition was taken) that plaintiff moved to amend his complaint to substitute the authentic purchase agreement for the bogus one. In the meantime, discovery had continued and a blizzard of legal documents had fallen. We single out four developments:
1. On February 24, Mobil threatened Monahan with franchise revocation based partly on his dealings with Aoude.
2. Aoude engaged new counsel.
3. On May 5, Aoude filed a second action in the same federal district court. The complaint in the “new” case adopted all the factual allegations made in the first case and prayed for essentially the same relief, but abandoned plaintiff’s earlier reliance on the phony contract. Then, citing Mobil’s February 24 letter to Monahan, the new complaint proceeded to allege violations of the Petroleum Marketing Practices Act (PMPA), 15 U.S.C. §§ 2801-2806 (1982).
4. On May 17, Mobil moved to dismiss both actions because of Aoude’s fraudulent practices.
We need not wax longiloquent as to ensuing events. On June 2, the district court granted preliminary injunctive relief in Mobil’s favor; 1 the court also denied plaintiff’s motion to substitute the authentic agreement for the ersatz one. Thereafter, the district court heard arguments on defendant’s dismissal motions and took them under advisement. Some months later, the court filed a memorandum decision dismissing both actions. In its rescript, the court observed that “plaintiff’s entire case rests on a false foundation.”
These appeals, one for each of plaintiff’s two suits, followed.
II
At the outset, we address the standard of review. We believe that the district courts must be accorded considerable latitude in dealing with serious abuses of the judicial process and that the trier’s determination to dismiss a case for such a reason should be reviewed only for abuse of discretion.
See, e.g., Link v. Wabash R.R. Co.,
While broad, the trial court’s discretion is not unlimited. The judge must consider the proper mix of factors and juxtapose them reasonably. “Abuse occurs when a material factor deserving significant weight is ignored, when an improper factor is relied upon, or when all proper and no improper factors are assessed, but the court makes a serious mistake in weighing them.”
Independent Oil and Chemical Workers of Quincy, Inc. v. Procter & Gamble Mfg. Co.,
Although dismissal need not be preceded by other, less drastic sanctions,
Farm Constr. Services, Inc. v. Fudge,
Ill
Exercising great circumspection, the court below suggested several sources from which it derived authority to enter the dismissal orders. We are not similarly inclined. It strikes us as elementary that a federal district court possesses the inherent power to deny the court’s processes to one who defiles the judicial system by committing a fraud on the court.
A.
A “fraud on the court” occurs where it can be demonstrated, clearly and convincingly, that a party has sentiently set in motion some unconscionable scheme calculated to interfere with the judicial system’s ability impartially to adjudicate a matter by improperly influencing the trier or unfairly hampering the presentation of the opposing party’s claim or defense.
See, e.g., Alexander v. Robertson,
Because corrupt intent knows no stylistic boundaries, fraud on the court can take many forms. In our estimation, however, the present case is a near-classic example of the genre.. Appellant’s bad faith is manifest. By Aoude’s own admission, he fabricated the purchase agreement; gave it to his lawyer; read the complaint before it was filed; realized that counsel, acting on his behalf, proposed to annex the bogus agreement to the complaint (thus representing it to be authentic); and nevertheless authorized the filing. Thereafter, Aoude and his counsel continued to act out the charade until, in the course of pretrial discovery undertaken by Mobil, Monahan revealed a glimmer of the truth. Even then, Aoude hedged his bets, forcing Mobil to piece together the sordid story bit by bit. Following Monahan’s deposition testimony, more than three months elapsed before plaintiff asked to amend his complaint to substitute the real agreement for the invented one. The only conceivable reason for Aoude’s elaborate duplicity was to gain unfair advantage, first in the dispute, thereafter in the litigation. The tactic plainly hindered defendant’s ability to prepare and present its case, while simultaneously throwing a large monkey wrench into the judicial machinery. In our view,
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this gross misbehavior constituted fraud on the court.
See Cleveland Demolition Co. v. Azcon Scrap Corp.,
B.
The next question, of course, requires that we examine the options of a federal district judge confronted by such odious machinations. It is apodictic that federal courts possess plenary authority “to manage their own affairs so as to achieve the orderly and expeditious disposition of eases.”
Link,
There is an irrefragable linkage between the courts’ inherent powers and the rarely-encountered problem of fraud on the court. Courts cannot lack the power to defend their integrity against unscrupulous marauders; if that were so, it would place at risk the very fundament of the judicial system. As Justice Black wrote in a case involving a not-dissimilar fraud:
[Tjampering with the administration of justice in the manner indisputably shown here involves far more than an injury to a single litigant. It is a wrong against the institutions set up to protect and safeguard the public, institutions in which fraud cannot complacently be tolerated consistently with the good order of society_ The public welfare demands that the agencies of public justice be not so impotent that they must always be mute and helpless victims of deception and fraud.
Hazel-Atlas Glass Co. v. Hartford-Empire Co.,
We find the caselaw fully consonant with the view that a federal district judge can order dismissal or default where a litigant has stooped to the level of fraud on the court. The Supreme Court said so in
Hazel-Atlas,
albeit in dicta.
Id.
at 250,
C.
Plaintiff offers a plethora of reasons why, even if the court had power to dismiss, the remedy ought not to have been employed in his case. We reject all of these asseverations, commenting briefly as to five of them.
1.
Materiality.
Plaintiff argues that his deceit, if not entirely excusable, falls short of furnishing a basis for dismissal since “[t]he attaching of the incorrect agreement to the Complaint ... did not in any way interfere with Mobil’s ability to litigate the case nor did it interfere in any way with the District Court’s ability to render a ‘rightful decision.’ ” Appellant’s Brief at 26. We disagree. The bogus agreement clearly had the capacity to influence the adjudication and to hinder Mobil’s presentation of its case. The failure of a party’s corrupt plan does not immunize the defrauder from the consequences of his misconduct. When Aoude concocted the agreement, and thereafter when he and his counsel annexed it to the complaint, they plainly thought it material. That being so, “[tjhey are in no position now to dispute its effectiveness.”
Hazel-Atlas,
2.
Right to a Hearing.
Appellant claims that the district court erred in not conducting an evidentiary hearing. He is wrong. In the first place, motions do not usually culminate in evidentiary hearings.
See
Fed.R.Civ.P. 43(e) (court may “hear” motion and determine ancillary facts on affidavits or depositions). Second, we regularly turn a deaf ear to protests that an evidentiary hearing should have been convened but was not, where, as here, the protester did not seasonably request such a hearing in the lower court. This appellant knows the rule at first hand.
See Aoude,
Here, the record before the trial court was compendious; the material facts were undisputed; notice and the opportunity for presentment were abundant (the district court entertained not only evidentiary submissions, such as deposition transcripts and affidavits, but briefs and oral arguments); and the court based its dispositive findings of fact largely on plaintiff’s own admissions. No more was required. 3
*1121
3.
Blaming the Lawyer.
Aoude’s argument that the district court unjustly visited the sins of counsel upon the client cannot withstand scrutiny. It may well be that there are cases where it would be inappropriate and a “deplorable kind of injustice” mechanically to hold litigants bound by every lawyerly misdeed, no matter how innocent the client or culpable the attorney.
Link,
4. Leave to Amend. Under the Civil Rules, leave to amend a complaint “shall be freely given when justice so re-quires_” Fed.R.Civ.P. 15(a). In June 1988, some six months after suit was started, the district court refused to allow appellant to scrap the bogus agreement and append the true agreement to the complaint in its place. This denial of his motion to amend, Aoude says, constituted an abuse of discretion. His position is unsupportable.
It is settled that a district court may deny a motion to amend in cases of “undue delay, bad faith or dilatory motive on the part of the movant.”
Foman v. Davis,
5. The Second Suit. Appellant remonstrates that, whatever disposition may be made of his original suit, his second suit was filed without any reference to the bogus agreement and should not have been dismissed. The assertion will not wash. A malefactor, caught red-handed, cannot simply walk away from a case, pay a new docket fee, and begin afresh. History is not so glibly to be erased. Once a litigant chooses to practice fraud, that misconduct infects his cause of action, in whatever guises it may subsequently appear. Thus, to the extent that the two complaints paralleled each other, the second suit was, for the reasons already stated, appropriately jettisoned.
To be sure, plaintiff’s second complaint can be read to allege an additional cause of action for PMPA violations based
*1122
on an event (the February 24 letter) which occurred after the first suit was started. That claim arguably constituted a separate cause of action.
Cf., e.g., Walsh v. International Longshoremen’s Ass’n,
IV
We need go no further. Appellant chose to play fast and loose with Mobil and with the district court. He was caught out. The judge considered the relevant factors and acted well within his discretion: appellant’s brazen conduct merited so extreme a sanction; Mobil, having undergone extra trouble and expense, had a legitimate claim to dismissal; and the court, jealous of its integrity and concerned about deterrence, was entitled to send a message, loud and clear.
Affirmed.
Notes
. In our earlier opinion, we upheld this injunction.
Aoude,
. In
Hazel-Atlas,
the relief awarded took the form of vacating a judgment long after it had become final, and prohibiting the judgment-holder from relitigating its claim.
. Because of (a) the prejudice accruing to defendant by reason of plaintiff's fraud, (b) the concomitant interference with the court’s adjudicatory function, (c) the public interest in the integrity of the judicial system, and (d) the centrality of the fraud to the matters at issue in the litigation, the dismissal orders did not contravene due process or conflict with what might remain of the "mere punishment” doctrine enunciated in
Hovey v. Elliott,
. In this connection, it is well to recall that PMPA "constituted a diminution of prior rights of franchisors and thus should not be extended beyond the Act’s language and purpose.”
Desfosses v. Wallace Energy, Inc.,
