Climate Scientist Defamation Ruling Could Affect Climate Debate

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By Rachel Leven

A climate scientist can proceed with his defamation suit against a free-market group that compared him to Jerry Sandusky, the convicted Penn State child molester, an appeals court ruled Dec. 22 in a case that some say could affect how debate over climate science is conducted.

“Would-be critics of climate change science would need to be more careful in how they level or express their criticism, making sure that whatever criticisms they level are based in fact and not merely in conjecture,” Joseph Russomanno, an associate professor for Arizona State University’s Walter Cronkite School of Journalism and Mass Communication, told Bloomberg BNA.

Jonathan Adler, director of the Center for Business Law and Regulation at the Case Western Reserve University School of Law, expressed concern about the court’s ruling: “We’re worried about the chilling effect.”

The ruling by the District of Columbia Court of Appeals, the court serving Washington, D.C., is the latest move in the case filed in October 2012 and amended in June 2013 by Michael Mann, a scientist who authored key climate studies that became the foundation for “the conclusion that the sharp increase in temperature starting in the twentieth century was anthropogenic.” Mann’s complaint centered on published statements by the Competitive Enterprise Institute (CEI) and others accusing him of “improperly manipulating data to reach a preordained conclusion, deception, fraud, and misconduct.”

Leaked E-Mails

Those assertions referenced leaked international climate e-mails, some of which were from Mann, in November 2009 that some interpreted to show fraudulent activity. However, claims of the fraudulent activity were thoroughly vetted and disproven by international and domestic government entities in 2010 and 2011. Mann asserted the defendants’ statements, some published by CEI and others by the National Review, were libelous and intentionally inflicted emotional distress on him.

More recently, the defendants moved to dismiss Mann’s complaint under the District of Columbia’s Anti-Strategic Lawsuits Against Public Participation, a law created to prevent groups or individuals on one side of a political or public policy debate from filing litigation to “punish or prevent the expression of opposing points of view.” Those motions were denied by the D.C. Superior Court in January 2014; subsequent motions on this issue also were denied and the defendants appealed.

On Dec. 22, the appeals court dismissed Mann’s defamation claim regarding an editorial published in the National Review and intentional infliction of emotional distress claim. However, it remanded for trial in the lower court the climate scientist’s defamation claims related to CEI, a free market group.

Acting ‘With Reckless Disregard’

“A jury could find, by clear and convincing evidence, that appellants ‘in fact entertained serious doubts’ or had a ‘high degree of awareness’ that the accusations that Dr. Mann engaged in scientific misconduct, fraud, and deception, were false, and, as a result, acted ‘with reckless disregard’ for the statements’ truth when they were published,” the court wrote in its order on the institute-related defamation allegation.

Mann’s attorney Peter Fontaine, who works in the Philadelphia offices of Cozen O’Connor and is co-chair of its climate change practice, told Bloomberg BNA the ruling “clears the path for a jury of peers to decide the claims.” Fontaine said his client would now evaluate next steps.

Andrew Grossman, the institute’s attorney and partner at Baker Hostetler, said in a statement that the group is “confident that Dr. Mann’s remaining claims will ultimately fail, because they attempt to shut down speech and debate that is absolutely protected by the First Amendment.”

“Today’s decision only draws out Dr. Mann’s years-long effort to wage ‘lawfare’ against his opponents instead of engaging in public debate,” Grossman said.

What It Means

While this order is procedural, the court clearly lays out its line of reasoning for why Mann could succeed in libel claims against CEI. Should the outcome from the trial follow the same line of reasoning, various academics and legal professionals disagreed on what the impact would be.

Adler argued the ruling could chill public debate over climate science, broader environmental science and more because it would inhibit questioning of whether investigations reached the right conclusions. He said comparing Mann to Sandusky was in poor taste, but threatening litigation over the questioning of investigations’ outcomes like those on the 2009 leaked e-mails was dangerous.

“It has to be part of the debate of the public figures,” Adler said.

But, Russomanno and Michael Gerrard, Andrew Sabin Professor of Professional Practice at Columbia Law School in New York, argued that the institute’s articles clearly attacked Mann’s professional integrity and those attacks weren’t based in fact. Libel law clearly protects individuals’ reputations, Russomanno said.

“Part of the thinking here is that once a reputation is damaged, you never get it back,” Russomanno said, adding that a court ruling in line with the appeals court’s order could remind skeptics of climate science to be careful to use facts. “I think this judgment from the D.C. Court of Appeals is a clear admonishment or scolding of some of the defendants in this case.”

Heartening to Climate Scientists

And then there is Gerrard, who sees the case as even narrower in impact. Should the jury in the lower court follow the appeals court’s lead, Gerrard told Bloomberg BNA, the impact would be limited to addressing the “particularly egregious claims” against Mann and not impact the climate science debate on the whole.

“It is unusual although certainly not unprecedented for these kinds of personal attacks of specific misconduct to be published against a respected scientist and when it does happen, the scientists usually turn the other cheek,” Gerrard, whose center hosts the Climate Science Legal Defense Fund that has worked with Mann on the case, but who hasn’t been involved in the case himself, said.

“Climate scientists are receiving a lot of unjustified blows and it’s heartening to see someone strike back,” Gerrard added.

To contact the reporter on this story: Rachel Leven in Washington, D.C. at

To contact the editor responsible for this story: Larry Pearl at

For More Information

The legal order is available at

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