Would accusing the opposing counsel of perpetuating a fraud on the court based on false material facts presented to the court be considered privileged?
Accusing opposing counsel of that in what way? If you put the claims in an appropriate motion to the court (e.g. a motion to set aside a judgment due to alleged fraud on the court), then the answer is generally yes, it is privileged.
But you also want to be sure your claim is well founded before making it. Accusing opposing counsel of fraud on the court is a serious accusation and should not be done lightly. Remember that just because you and the opposing side see the facts differently does not mean the other side is committing any fraud or perjury, let alone a fraud on the court. The whole reason we have trials in civil cases is for the jury (or judge if there is no jury) to sort out what the actual facts of the case are. If there were no dispute over the facts then the case gets resolved by the judge in summary judgment. So it takes more than just a dispute over the facts to give rise to a fraud on the court.
Indeed, in federal courts the term "fraud on the court" refers to a scheme or plan that attacks the integrity of the court itself; one designed to interfere with the court's decision making or the usual functioning of the court. A federal district Court in California gave a fairly detailed overview of what fraud on the court is:
Fraud on the court “‘embrace[s ] only that species of fraud which does or attempts to, defile the court itself, or is a fraud perpetrated by officers of the court so that the judicial machinery can not perform in the usual manner its impartial task of adjudging cases that are presented for adjudication.’ ” Appling, 340 F.3d at 780 (quoting In re Levander, 180 F.3d at 1119) (alteration in original). A finding of fraud on the court “must involve an unconscionable plan or scheme which is designed to improperly influence the court in its decision.” Pumphrey v. K.W. Thompson Tool Co., 62 F.3d 1128, 1131 (9th Cir.1995) (internal quotations marks omitted); see also Appling, 340 F.3d at 780 (“Fraud on the court requires a ‘grave miscarriage of justice,’ and a fraud that is aimed at the court.” (quoting Beggerly, 524 U.S. at 47, 118 S.Ct. 1862)).
“In determining whether fraud constitutes fraud on the court, the relevant inquiry is not whether fraudulent conduct ‘prejudiced the opposing party,’ but whether it “harm[ed]” the integrity of the judicial process.' ” Estate of Stonehill, 660 F.3d at 444 (quoting Alexander v. Robertson, 882 F.2d 421, 424 (9th Cir.1989)); see also Estate of Stonehill, 660 F.3d at 444 (“Fraud on the court involves ‘far more than an injury to a single litigant....’ ” (quoting Hazel–Atlas Glass Co., 322 U.S. at 246, 64 S.Ct. 997)). Although “one of the concerns underlying the ‘fraud on the court’ exception is that such fraud prevents the opposing party from fully and fairly presenting his case,” this showing alone is not sufficient. Abatti, 859 F.2d at 119; see also Abatti, 859 F.2d at 118 (“[W]e have said that it may occur when the acts of a party prevent his adversary from fully and fairly presenting his case or defense.... Fraud on the court must involve ‘an unconscionable plan or scheme which is designed to improperly influence the court in its decision.’ ” (quoting Toscano v. Comm'r of the I.R., 441 F.2d 930, 934 (9th Cir.1971) (internal citation omitted) (emphasis added))). At the same time, a showing of prejudice to the party seeking relief is not required. Dixon, 316 F.3d at 1046.
“Non-disclosure, or perjury by a party or witness, does not, by itself, amount to fraud on the court.” Appling, 340 F.3d at 780; accord In re Levander, 180 F.3d at 1119 (“Generally, non-disclosure by itself does not constitute fraud on the court.... Similarly, perjury by a party or witness, by itself, is not normally fraud on the court.”); see also Hazel–Atlas Glass Co., 322 U.S. at 245, 64 S.Ct. 997 (“This is not simply a case of a judgment obtained with the aid of a witness who, on the basis of after-discovered evidence, is believed possibly to have been guilty of perjury.”).
The Supreme Court has held that a party's failure to “thoroughly search its records and make full disclosure to the Court” does not amount to fraud on the court. Beggerly, 524 U.S. at 47, 118 S.Ct. 1862 (internal quotation marks omitted); see also Valerio v. Boise Cascade Corp., 80 F.R.D. 626, 641 (C.D.Cal.1978), adopted as the opinion of the Ninth Circuit in 645 F.2d 699, 700 (9th Cir.1981) (“[N]ondisclosure to the court of facts allegedly pertinent to the matter before it, will not ordinarily rise to the level of fraud on the court.”).
United States v. Sierra Pac. Indus., 100 F. Supp. 3d 948, 955–56 (E.D. Cal. 2015), aff'd sub nom. United States v. Sierra Pac. Indus., Inc., 862 F.3d 1157 (9th Cir. 2017).
The Ninth Circuit Court of Appeals, which is the federal appeals court that hears appeals from federal district courts in California, echoes that discussion in a more abbreviated summary of what constitutes fraud on the court:
Simply put, not all fraud is fraud on the court. To constitute fraud on the court, the alleged misconduct must “harm[ ] the integrity of the judicial process.” Alexander v. Robertson, 882 F.2d 421, 424 (9th Cir.1989). To determine whether there has been fraud on the court, this circuit and others apply Professor Moore's definition:
“Fraud upon the court” should, we believe, embrace only that species of fraud which does or attempts to, defile the court itself, or is a fraud perpetrated by officers of the court so that the judicial machinery can not perform in the usual manner its impartial task of adjudging cases that are presented for adjudication.
Gumport v. China International Trust and Inv. Corp. (In re Intermagnetics America, Inc.), 926 F.2d 912, 916 (9th Cir.1991) (quoting 7 James Wm. Moore et al., Moore's Federal Practice ¶ 60.33, at 515 (2d ed. 1978)).
In re Levander, 180 F.3d 1114, 1119 (9th Cir. 1999).
Fraud on the court must be proven at a higher burden of proof, too. "Fraud on the court must be proven by clear and convincing evidence." Aulmann v. Aulmann, 25 F. App'x 555, 556–57 (9th Cir. 2001).
I see a lot of pro se parties throw around the term "fraud on the court" without knowing what that term really means. It is a phrase with a particular meaning — not every false statement, perjury, or fraud that might be committed during the course of litigation is going to be a fraud on the court. It takes something more than that to reach the level of fraud on the court.
If you and the opposing side simply differ on what you think the facts are, that is not fraud on the court. If you think you can show that a fact asserted by the other side is false, you demonstrate that at trial and try to convince the court that your version of the facts is the correct one. Again, that is why we have trials.
It takes something extraordinary to be a fraud on the court.