Michael Mann, formerly a climate scientist at Penn State University, is no stranger to controversy.[1] As an outspoken advocate for climate change, he has attracted close scrutiny and harsh criticism. Several right-of-center commentators criticized Mann’s work in potentially defamatory terms of “misconduct,” or “manipulation,” or data torturing. One blogger likened Mann’s conduct to Penn State’s Jerry Sandusky’s sexual abuse scandal.[2]
Mann sought vindication, not by a duel, but by lawsuits for defamation. His cases have bounced up and down the court system for over a decade,[3] but last week, they crashed landed. In the course of yo-yo’ing through the courts, the case resulted in the Supreme Court’s denial of a petition for a writ of certiorari, which was accompanied by a dissent from Associate Justice Alito. The published dissent is interesting for the light it sheds on recent speculation about the fate of New York Times v. Sullivan,[4] but also for providing a reasonably accurate statement of the facts of the case:
“Penn State professor Michael Mann is internationally known for his academic work and advocacy on the contentious subject of climate change. As part of this 345*345 work, Mann and two colleagues produced what has been dubbed the ‘hockey stick’ graph, which depicts a slight dip in temperatures between the years 1050 and 1900, followed by a sharp rise in temperature over the last century. Because thermometer readings for most of this period are not available, Mann attempted to ascertain temperatures for the earlier years based on other data such as growth rings of ancient trees and corals, ice cores from glaciers, and cave sediment cores. The hockey stick graph has been prominently cited as proof that human activity has led to global warming. Particularly after emails from the University of East Anglia’s Climate Research Unit were made public, the quality of Mann’s work was called into question in some quarters.
Columnists Rand Simberg and Mark Steyn criticized Mann, the hockey stick graph, and an investigation conducted by Penn State into allegations of wrongdoing by Mann. Simberg’s and Steyn’s comments, which appeared in blogs hosted by the Competitive Enterprise Institute and National Review Online, employed pungent language, accusing Mann of, among other things, ‘misconduct’, ‘wrongdoing’, and the ‘manipulation’ and ‘tortur[e]’ of data. App. to Pet. for Cert. in No. 18-1451, pp. 94a, 98a (App.).
Mann responded by filing a defamation suit in the District of Columbia’s Superior Court. Petitioners moved for dismissal, relying in part on the District’s anti-SLAPP statute, D. C. Code § 16-5502(b) (2012), which requires dismissal of a defamation claim if it is based on speech made ‘in furtherance of the right of advocacy on issues of public interest’ and the plaintiff cannot show that the claim is likely to succeed on the merits. The Superior Court denied the motion, and the D. C. Court of Appeals affirmed. 150 A.3d 1213, 1247, 1249 (2016). The petition now before us presents two questions: (1) whether a court or jury must determine if a factual connotation is ‘provably false’ and (2) whether the First Amendment permits defamation liability for expressing a subjective opinion about a matter of scientific or political controversy. Both questions merit our review.”[5]
Subsequent events in the Mann case have made a return trip to the Supreme Court for a substantive decision on the First Amendment issue very unlikely. Mann’s case against the National Review was dismissed before trial. A District of Columbia jury returned verdicts in favor of Mann, and against Steyn and Simberg, on Mann’s claims of libel. The jury awarded Mann two dollars, one dollar against each defendant, but one million dollars against Steyn, and one thousand dollars against Simberg, as punitive damages. Post-trial motions have been pending after the trial until earlier this month.[6]
On January 7, 2025, the trial court ordered Dr. Mann to pay court costs and attorney fees in the amount $530,820.21 to The National Review, which had been dismissed from the case, before trial.[7] Mann plans to appeal this cost award against him.
Punitive Damages
Judge Irving upheld the libel verdict for Dr. Mann, but found that the punitive damages awards were grossly excessive given the nominal damage awards.[8] As such, the punitive damage awards offended the due process clause of the constitution, and had to be reduced.[9] The one million dollar award was reduced to $5,000.
Sanctions against Michael Mann for Misconduct
In the course of the trial, Dr. Mann and his counsel introduced an exhibit with items of alleged damages in the form of loss grants.[10] In the pre-trial discovery phase of the case, Mann had not been able to adduce any evidence that he actually lost any funding because grants withheld or withdrawn because of the comments of the two blogging defendants. Mann had acknowledged, at least at one point, that the details of grants not received were not relevant to any claim or defense in the case. Understandably, Judge Alfred S. Irving, Jr., presiding, was rather upset about the Mann testimony and exhibit. The defendants filed a “Motion for Sanctions for Bad-Faith Trial Misconduct,” during the trial.[11]
The facts of the motions were further litigated in post-trial motions, with the result that Judge Irving found, by clear and convincing evidence, that Dr. Mann and his counsel had acted in bad faith in pressing claims for several lost grants. In last week’s 46-page Order, Judge Irving documented in painful detail the dishonesty and mendacity exhibited by Mann and his lawyers, and the violation of multiple rules of professional responsibility. The court found that Dr. Mann, through his lawyers, had:
“acted in bad faith when they presented erroneous evidence and made false representations to the jury and the Court regarding damages stemming from loss of grant funding… . The Court does not reach this decision lightly.”
Judge Irving characterized the misconduct of Dr. Mann and his counsel as “extraordinary in its scope, extent, and intent.” The court has not yet made an assessment of the dollar amount for Mann’s egregious conduct. In all likelihood, the sanction award for his trial misconduct will exceed the $6,002, he has in the plus column for his litigation efforts. With over a half a million dollars assessed against Dr. Mann, in favor of the National Review, Mann’s litigation efforts to date might seem like being hit over the head repeatedly with a hockey stick.
Over a year ago, the New York Times reported on the initial jury verdict in favor of Dr. Mann.[12] Since then, however, the paper has been remarkably silent on the developments in the case, including the court’s findings concerning Dr. Mann’s misconduct in presenting evidence.
No one will miss the irony in Mann’s prevailing at trial in showing that he had been defamed by the trial defendants, and then attempting in plain sight to deceive the jury on damages, in what fair comment might call “misconduct,” or “manipulation,” or “data torturing.” Of course, none of the litigation events described by Judge Irving bear on the correctness vel non of predictions of climate change. These litigation events do, however, single out Dr. Michael Mann as lacking the ethos for serving as a spokesman for any scientific claim. Being called out for manipulating evidence is not a good thing for anyone in the evidence business.
[1][1] Mann left Penn State in 2022, to become a Presidential Distinguished Professor in the Department of Earth and Environmental Science at the University of Pennsylvania.
[2] See Competitive Enterprise Institute v. Mann (D.C. Ct. Apps. 2016).
[3] See “Oreskes Excluded as Historian Expert Witness in Mann Case,” Tortini (Feb. 28, 2023); “Climategate on Appeal,” Tortini (Aug. 17, 2014).
[4] 376 US 254 (1964).
[5] National Review, Inc. v. Mann, 140 S.Ct. 344, 344-45 (2019).
[6] Eugene Volokh, “Punitive Damages Award in Mann v. Steyn Reduced from $1M to $5K, largely because the compensatory damages were just $1,” Reason (Mar. 4, 2025); Roger Pielke, “In Bad Faith,” AEI (Mar. 12, 2025).
[7] Mann v. National Review, Inc., 2012 CA 008263B, Amended Order Granting in Part National Review Inc.’s Motion for Attorneys’ Fees and Supplemental Motion for “Fees on Fees” (D.C. Super. Ct. Jan. 7, 2025); see Danielle Shockey, “Pennsylvania Climate Scientist Must “Pay Up” $530K After 8 Year Legal Battle Over 2 Blog Posts,” Tampa Free Press (Jan. 12, 2025); Marc Morano, “Prof. Michael Mann ‘intends to appeal’ court order to pay ‘National Review Inc. $530,820.21 in attorneys’ fees & costs’,” Climate Depot (Jan. 10, 2025).
[8] Mann v. National Review, Inc., 2012 CA 008263B, Omnibus Order on Defendants’ Post-Trial Motions for Judgment as a Matter of Law (D.C. Super. Ct. Mar. 4, 2025).
[9] Id. at 20-30. See BMW of North America v. Gore, 517 U.S. 559, 575 (1996); Cooper Indus., Inc. v. Leatherman Tool Group, Inc., 532 U.S. 424, 433 (2001); State Farm Mut. Auto. Ins. Co. v. Campbell, 538 U.S. 408, 427 (2003).
[10] Mann v. National Review, Inc., 2012 CA 008263B, Order Granting in Part Defendants’ Motions for Sanctions (D.C. Super. Ct. Mar. 12, 2025).
[11] Id. at 1-2.
[12] Delger Erdenesanaa, “Michael Mann, a Leading Climate Scientist, Wins His Defamation Suit,” N.Y. Times (Feb. 8, 2024).