Scientist Michael Mann, whose work on climate change led to contentious litigation over access to his emails, filed a libel lawsuit Monday against National Review, accusing the conservative publication of defaming him by accusing him of academic fraud.

In the complaint filed in District of Columbia Superior Court, Mann, director of the Earth System Science Center at Pennsylvania State University, claimed that a July 15 article not only falsely accused him of misconduct but crossed a line by comparing him to Jerry Sandusky, the former Penn State football assistant coach convicted of child molestation. He also sued the Competitive Enterprise Institute, a think tank that ran a piece about Mann on its staff blog, OpenMarket.org.

Mann was one of the researchers behind the now-famous “hockey stick” graph showing a jump in global temperature at the end of the last millennium. He was a professor at the University of Virginia from 1999 to 2005 and became the subject of litigation when the Virginia attorney general’s office launched an investigation into his use of government grant money. Mann and his supporters charged that the investigation was part of a politically motivated effort to discredit climate change science.

The National Review article at issue by writer Mark Steyn, entitled “Football and Hockey,” called Mann “the man behind the fraudulent climate-change ‘hockey-stick’ graph.” After emails surfaced that raised concerns about data manipulation by climate change scientists, including Mann, Steyn questioned the reliability of a Penn State investigation that cleared Mann of wrongdoing. He noted that the Mann investigation and a university inquiry into Sandusky’s behavior both took place under former President Graham Spanier. “And, as with Sandusky and [former football coach Joe] Paterno, the college declined to find one of its star names guilty of any wrongdoing,” Steyn wrote.

Steyn referenced a July 13 article by Rand Simberg on the Competitive Enterprise Institute’s blog that speculated that Mann “could be said to be the Jerry Sandusky of climate science, except that instead of molesting children, he has molested and tortured data in the service of politicized science that could have dire economic consequences for the nation and planet.”

A current version of the article no longer includes the line as quoted in Steyn’s piece. Steyn and Simberg are named as defendants in Mann’s lawsuit.

“If an institution is prepared to cover up systemic statutory rape of minors, what won’t it cover up?” Steyn wrote. “Whether or not he’s ‘the Jerry Sandusky of climate change,’ he remains the Michael Mann of climate change, in part because his ‘investigation’ by a deeply corrupt administration was a joke.”

‘Comes with the territory’

In a July 23 letter to National Review, Mann’s lawyer, John Williams of Cozen O’Connor, asked that the piece be removed.

In an August 22 article, National Review editor Rich Lowry wrote that they would welcome a lawsuit as a way to further investigate Mann through discovery. The Competitive Enterprise Institute also rejected Mann’s request for a retraction.

In the complaint, Mann cited several reports, including a 2011 report by the inspector general of the National Science Foundation, finding no evidence of misconduct by Mann. He accused National Review and the Competitive Enterprise Institute of publishing false information with “actual malice and wrongful and willful intent to injure Dr. Mann.”

Mann and Williams could not be reached for comment, but Mann posted a statement about the lawsuit on his Facebook page: “Despite their knowledge of the results of these many investigations, the defendants have nevertheless accused Dr. Mann of academic fraud and have maliciously attacked his personal reputation with the knowingly false comparison to a child molester.”

Lead counsel for National Review and the Competitive Enterprise Institute, David Rivkin Jr. of Baker Hostetler, said today that, “This lawsuit is without merit, and we are confident we will prevail.”

Sam Kazman, general counsel for the Competitive Enterprise Institute, said today that Mann’s lawsuit “is an unfounded attempt to squelch open debate over global-warming issues.” He added that Mann is a public figure, so “this sort of debate comes with the territory.”

The case is before Judge Natalia Combs Greene. An initial scheduling conference is scheduled for January 25.