Pundits, politicians, and writers on the Right have long sought to undermine the credibility of climate science, but a recent court ruling has finally held two of them accountable for crossing the line from questioning the science to defaming the scientist behind it. Rand Simberg, a former adjunct scholar at the Competitive Enterprise Institute (CEI), and Mark Steyn, a contributor to National Review, were found guilty by a Washington D.C. jury of defaming climate scientist Michael Mann in a case that took a dozen years to wind its way through the courts. 

Mann rose to prominence for his 1998 “hockey stick” chart, which depicted the sharp rise in post–Industrial Revolution global temperatures compared with the previous millennium—disproving the idea that late–twentieth century warming was part of a normal cycle of temperature changes. The graph, which was used in early Intergovernmental Panel on Climate Change reports and validated many times over, provided a stark visual warning of the looming climate emergency and was intended to galvanize the public into action. It also galvanized critics like Simberg, who in 2012 accused Mann, then a professor at Penn State, of data “molestation” akin to the child molestation perpetrated by disgraced Penn State coach Jerry Sandusky. 

Simberg’s post came after the release of leaked emails between Mann and other scientists about their research. Taken out of context, the scientists’ comments about how best to present their data and account for anomalies in it were seized on by climate skeptics as evidence of a giant hoax. Simberg’s blog post for CEI—a think tank that champions climate denialism—was later quoted by Steyn in an online post for National Review that compared Penn State’s cover-up of the Sandusky scandal to the university’s investigation into Mann’s emails. Penn State, as well as the other seven academic and governmental panels investigating the matter, found no evidence that Mann had fraudulently manipulated data.

Despite requesting more than one million pages of documents, National Review failed to identify a single document supporting their allegation of deception on Mann’s part; witnesses for the defense were similarly unable to provide any evidence, even admitting that Mann “had not engaged in research misconduct.” Though conservatives often defend such reckless slander as an expression of “free speech,” in this case the overwhelming evidence that Mann’s methods were legitimate and his conclusions sound meant that the statements at issue met the high bar for actual malice. While Mann only sued for $1 in compensatory damages, the court also ordered Steyn to pay $1,000 and Simberg to pay $1,000,000 in punitive damages as a deterrent. 

Will it actually deter anyone? While Simberg and Steyn were found guilty, the publications they wrote for have thus far evaded liability, though Mann’s attorney has promised to pursue further claims against them. A clear-cut case that took twelve years to play out probably won’t stop climate skeptics from making other, more ambiguous claims to muddy the waters and sow confusion among the public. Nor can we expect the jury’s verdict to turn back the growing post-pandemic wave of skepticism toward scientists and their work. 

Still, holding Simberg and Steyn accountable is important. Though their attacks occurred in 2012, the trend of harassing, defaming, or even threatening scientists whose conclusions don’t align with the Right’s agenda has only intensified. In a media landscape where a significant portion of the country is unlikely to trust—or even see—a scientifically backed assessment of the climate crisis, the influence of disinformation from right-wing media can feel untouchable. This case proves it is not.