The Supreme Court on Friday will consider whether to take up a prominent climatologist's defamation suit against a venerated conservative magazine, in a case that pits climate scientists against the free speech rights of global warming skeptics.

The dispute between scientist Michael Mann and the National Review has drawn attention from lawmakers, interest groups, academics and media, as the court weighs adding a potentially blockbuster First Amendment showdown to an already politically charged docket.

Scientists hail Mann’s lawsuit as a necessary defense against efforts to erode public confidence in the scientific consensus that climate change is an urgent threat, while free speech advocates have rallied around the iconic conservative publication.

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The case has made for strange bedfellows, with the National Review receiving backing from the Center for Investigative Reporting, which has produced award-winning coverage of climate change; Senate Majority Leader Mitch McConnell Addison (Mitch) Mitchell McConnellDemocratic senator to party: 'A little message discipline wouldn't kill us' House to vote on resolution affirming peaceful transition of power Republican lawyers brush off Trump's election comments MORE (R-Ky.); The Washington Post; and the American Civil Liberties Union (ACLU).

“The only way to protect free speech for our allies is to protect it for our adversaries,” Arthur Spitzer, ACLU D.C.’s legal director, told The Hill. “Today it’s unacceptable to deny climate change, but yesterday it was unacceptable to deny that homosexuality was sinful, and tomorrow it may be unacceptable to deny that robots are better parents than humans.”

Mann, the plaintiff, gained renown among climate scientists in the late 1990s for his “hockey stick” graph, which showed a sharp uptick in the earth’s temperatures over the 20th century as carbon emissions from human activity were also on the rise.

He later came under fire from skeptics after leaked emails with colleagues fueled accusations of misconduct, in a controversy dubbed “Climategate.” But in 2010, Mann’s employer, Penn State University, cleared the research professor of wrongdoing.

The National Review questioned the decision, though, accusing the school of a whitewash, and Mann of scientific fraud. Writers likened Mann to “the Jerry Sandusky of climate science,” a reference to the then-recently convicted serial pedophile and former football coach at Penn State.

In a post for the National Review, Steyn quoted the work of a blogger at the libertarian think tank Competitive Enterprise Institute, another party to the suit, who said of Mann: "Instead of molesting children, he has molested and tortured data."

Mann, who was cleared of wrongdoing in several separate investigations, threatened legal action if the accusations of data manipulation and misconduct were not retracted.

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In an abrasive response, National Review editor Rich Lowry penned an article bearing the headline "Get Lost." Practically taunting Mann to sue, Lowry said the magazine looked forward to prying additional documents through the discovery process because it would only discredit Mann further.

“He’s going to go to great trouble and expense to embark on a losing cause that will expose more of his methods and maneuverings to the world,” Lowry wrote. “In short, he risks making an ass of himself. But that hasn’t stopped him before.”

Mann’s litigation threat was not an idle one: He sued for defamation in D.C. court in 2012. In response, the magazine argued Mann was violating D.C.’s anti-SLAPP law, which aims to swat away lawsuits that target speech about matters of public interest.

By winter of 2016, D.C.’s high court dismissed the National Review’s argument. Mann’s defamation suit could proceed, a judge ruled.

This May, the magazine appealed to the Supreme Court. The justices will meet on Friday to consider whether to take the case. The court could grant or deny the appeal — or delay a decision.

As they deliberate, the justices may consider briefs from nearly two dozen GOP senators, a trio of former Republican attorneys general and a slate of libertarian and conservative groups, all of whom support the magazine’s appeal. The groups warn of a chilling effect on speech if the justices allow the D.C. court’s ruling against the writers to stand.

Twenty-one senators, including McConnell, Sens. Marco Rubio Marco Antonio RubioGOP lawmakers distance themselves from Trump comments on transfer of power McConnell pushes back on Trump: 'There will be an orderly transition' Graham vows GOP will accept election results after Trump comments MORE (R-Fla.) and Ted Cruz Rafael (Ted) Edward CruzCrenshaw looms large as Democrats look to flip Texas House seat SCOTUS confirmation in the last month of a close election? Ugly The Hill's Morning Report - Sponsored by Facebook - Trump previews SCOTUS nominee as 'totally brilliant' MORE (R-Texas), warned the justices that a failure to act would sharply curtail “vigorous debate” over public policy.

“It requires that speakers be given leeway to express their opinions forcefully and colorfully, without fear that hyperbole, analogy, or over-the-top rhetoric will land them in court,” the senators wrote. “The decision below lost sight of these basic principles. Left uncorrected, it will erode the freedom of political speech that lies at the foundation of our constitutional order.”

The ACLU sounded a similar note.

“Society can’t progress unless people are free to express and consider heretical ideas,” Spitzer said, “because there’s no way to predict which heretical ideas will be tomorrow’s truths.”

Mann, for his part, still seeks vindication.

“I do not believe I am ‘on the offensive,’ ” Mann told The Hill. “But rather I’m protecting my good name and reputation against false and defamatory statements about my research.”

The Hill spoke to a half-dozen climate scientists who expressed near-unanimous support for Mann’s lawsuit.

Paul Bledsoe, who served as communications director of the White House Climate Change Task Force under former President Clinton, said Mann’s litigation is crucial to stop the gagging of scientists who are informing the public about the need to act quickly to prevent an environmental catastrophe.

"Libelous personal attacks on climate scientists have been a key part of the skullduggery of far-right wing climate denying thugs and their funders for many years,” Bledsoe said. “They have only grown more prominent as the science of the climate crisis itself has become completely undeniable."

It is unclear whether the Supreme Court will muster the four votes needed to take up the case.

In her 2016 opinion, Judge Vanessa Ruiz of the D.C. Court of Appeals, a Clinton appointee, wrote that a reasonable jury could likely conclude that the conservative writers’ allegations against Mann were more akin to statements of fact, rather than constitutionally protected opinion.

Ruiz also appeared to give substantial weight to the numerous investigations that cleared Mann’s name following the “Climategate” episode.

Jonathan Adler, a law professor at Case Western Reserve University, said Mann v. National Review raises important First Amendment issues for the Supreme Court to consider.

“In my view, the D.C. courts adopted an unduly constrained view of what sorts of opinions may be expressed about contentious matters,” he said. “This could unduly chill critical speech about public figures.”

But other legal experts were skeptical the court would agree to hear the case, delivering another win for Mann.

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Rodney Smolla, a First Amendment and defamation law expert and litigator, said the Supreme Court is “unlikely to have any appetite” to draw legal lines between opinion and fact in the context of climate change.

“While predicting the actions of the court is probably a less exact science than the science of climate change,” Smolla said, “I will be surprised if the court grants review in this case.”

This story was updated on Nov. 25 at 1:20 p.m.