In a legal first, a federal appeals court ruled on Thursday that a climate science researcher can proceed with defamation claims against writers who made false allegations about his scientific work.

The ruling by the Court of Appeals for the District of Columbia, found that a "reasonable jury" could find that two writers defamed Michael Mann — known for the famous "hockey stick" graph showing that modern climate change is unprecedented in human history — by making false claims about his work, and comparing him to a notorious child molester.

SEE ALSO: Climate scientist who got death threats says he fears more attacks under Trump

The court found that two writers for the National Review and the Competitive Enterprise Institute, a conservative think tank, may have defamed Mann by comparing him to Penn State football coach Jerry Sandusky, who was convicted of molesting dozens of children in 2012.

Mann has been the subject of extraordinary criticism since his research was used as part of the foundation of a 2001 climate science report that found that human-caused emissions of greenhouse gases are the most likely cause of global warming.

Scientists at a rally in San Francisco on Dec. 13, 2016, protesting the incoming Trump administration. Image: Marcio Jose Sanchez/AP

Other climate scientists have been subjected to similar criticism and even death threats over their work. The court's decision, which now allows Mann to proceed with a defamation case against CEI and the National Review, comes less than a month before the climate-denying Trump administration comes to power.

Employees from CEI, including Chris Horner, are on Trump's transition team for the EPA, raising concerns that harassment of climate scientists could become official government policy. Horner, for example, has spent years filing lawsuits against climate scientists, seeking email records and other information to prove allegations of research misconduct.

The case, which specifically concerns articles that appeared on the CEI website and in the conservative publication National Review, will now be remanded to a lower court for trial.

And the ruling may have wide-reaching implications.

The case may lay the groundwork for future lawsuits brought by climate scientists and scientists in other hotly contested fields who believe their reputations were damaged by press reports and even organized misinformation campaigns.

The opinion, written for the three judge panel by Senior Judge Vanessa Ruiz, states:

To the extent statements in appellants’ articles take issue with the soundness of Dr. Mann’s methodology and conclusions — i.e., with ideas in a scientific or political debate — they are protected by the First Amendment. But defamatory statements that are personal attacks on an individual’s honesty and integrity and assert or imply as fact that Dr. Mann engaged in professional misconduct and deceit to manufacture the results he desired, if false, do not enjoy constitutional protection and may be actionable.

The court's majority opinion also found that making statements to gain advantage in a "no-holds-barred debate over global warming" are typically protected under the First Amendment. However:

... If the statements assert or imply false facts that defame the individual, they do not find shelter under the First Amendment simply because they are embedded in a larger policy debate.

Mann said he is "pleased" with the decision, and looking forward to moving on to a jury trial.

"We are particularly pleased that the court, after performing an independent review of the evidence, found that the allegations against me have been 'definitively discredited,'" he said in a statement.

While the climate wars that flared up during the George W. Bush administration subsided under President Barack Obama, scientists are girding for battle again, now that President-elect Trump appointed climate deniers to lead each of the environment-related cabinet agencies.

Mann himself has warned of what is to come, writing an op-ed in the Washington Post last week that he and his colleagues are now "bracing for a renewed onslaught of intimidation, from inside and outside government," given the coming changes in Washington.

"I fear the chill that could descend," he wrote.