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Penn professor Michael Mann was awarded more than $1 million in a defamation lawsuit last week.

Credit: Kylie Cooper

Penn professor Michael Mann was awarded more than 1 million dollars in a defamation lawsuit settled last week.

Mann — a professor in the department of Earth and Environmental Sciences — won the lawsuit against bloggers Rand Simberg and Mark Steyn last Thursday. The case argued that Simberg, a former adjunct fellow at the Competitive Enterprise Institute, and Steyn, a contributor to the National Review, had defamed him in a series of blog posts discrediting his climate change research in 2012. 

In a statement to The Daily Pennsylvanian, Mann wrote, “there was no question” that the trial took time out of his schedule, adding that he would have rather spent the time mentoring students or teaching. 

“But there was an important principle at stake here, and I had to see this through to its (fortunately, successful) conclusion,” Mann added. 

Mann first filed the suit in 2012 following the publication of Steyn and Simberg's blog. The pair claimed that Mann had manipulated his data and compared him to Jerry Sandusky, a convicted child molester who served as a football coach at Penn State. They also drew special attention to Mann’s “Hockey Stick” graph which depicted rising historical temperatures, and accused him of “scientific and academic misconduct.”

Pete Fontiane, a lawyer who represented Mann, called the decision a “big victory for truth and scientists everywhere” in a written statement sent to the DP. “[The] verdict vindicates Mike Mann’s good name and reputation,” Fontaine added. 

During the trial, both Steyn and Simberg testified that they believed what they wrote in the blog post, according to The New York Times.

“We always said that Mann never suffered any actual injury from the statement at issue. And today, after twelve years, the jury awarded him one dollar in compensatory damages,” Melissa Howes, Steyn’s manager, wrote to the DP. “The punitive damage award of one million dollars will have to face due process scrutiny under U.S. Supreme Court precedent," Howes added. 

An attorney for Simberg did not respond to a request for comment by the time of publication. 

Mann taught at Penn State for 17 years before beginning his tenure at Penn in 2022 and is regarded as “among the world's most renowned climate scientists,” according to NPR. His X account, the platform formerly known as Twitter, has more than 200,000 followers.

In addition to his professorship, Mann serves as the director of the Penn Center for Science, Sustainability, and the Media. According to its website, the center “focuses on the challenges and opportunities in communicating climate and environmental sustainability to the public and policymakers.”

While Mann wrote that he “wouldn’t expect or want” the University to be formally involved with the lawsuit and its subsequent proceedings, “the outpouring of support from my colleagues here at Penn has reinforced the strong affinity I have for this particular institution.” 

The six-person jury reached a unanimous decision following the monthlong trial in the District of Columbia Superior Court. Simberg and Steyn were each found guilty of defamation and were ordered to pay one dollar each in compensatory damages and $1 million and $1,000 in punitive damages, respectively.