Embattled Climate Scientist Michael Mann Wins $1 Million in Defamation Lawsuit

Michael Mann secured a win in his legal battle against conservative bloggers who said the climatologist “molested and tortured data” and compared him to a convicted child abuser

Michael Mann sitting in a blue suit holding a microphone

Michael E. Mann.

Join Our Community of Science Lovers!

CLIMATEWIRE | Climate scientist Michael Mann on Thursday secured a win in his long-running legal battle against conservative bloggers who once compared him to a convicted child abuser.

After a four-week trial, a D.C. Superior Court jury awarded the climatologist $1 million after finding that Rand Simberg, writing for the Competitive Enterprise Institute, and Mark Steyn, writing for the National Review, had defamed Mann in blog posts published in 2012. They accused Mann of manipulating the science around his “hockey stick” graph illustrating the exponential rise of global temperatures.

“I hope this verdict sends a message that falsely attacking climate scientists is not protected speech,” Mann said in a statement.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


In a column posted in 2012 on the CEI website, Simberg had referred to Mann as “the Jerry Sandusky of climate science,” comparing him to a former Pennsylvania State University football coach who was arrested for sexually abusing young boys. Simberg said Mann had “molested and tortured data” on climate change.

Steyn later quoted Simberg’s column in a post for the National Review.

Mann sued Simberg and Steyn after their articles were published. The case has had a long journey through the courts, landing before the Supreme Court in 2019.

The justices declined petitions from CEI and the National Review to stop Mann’s case from advancing the Washington court, claiming First Amendment protections. Justice Samuel Alito said he would have taken the case, writing at the time that “a question of this nature deserves a place on our docket.”

CEI declined to comment on the D.C. Superior Court’s Thursday decision. Steyn’s manager, Melissa Howes, released a statement suggesting that her client would appeal the $1 million the court awarded to Mann.

Conservatives had framed Mann’s trial as though climate science itself were taking the stand.

“Climate Change Is ON TRIAL,” Ann McElhinney, the Irish filmmaker behind the documentary “Frack Nation,” wrote Jan. 11 on X, the social media platform formerly known as Twitter.

“Michael Mann & Mark Steyn will battle in court,” she continued. “The case will explore the hockey stick climate graph that rattled the world. Mark Steyn claims it’s a fraud. Michael Mann believes it is our future.”

An attorney for Mann said the writings from Simberg and Steyn had knowingly caused the climate scientist personal and professional harm.

“Today’s verdict vindicates Mike Mann’s good name and reputation,” said Pete Fontaine, chair of the environmental practice at the law firm Cozen O’Connor. “It also is a big victory for truth and scientists everywhere who dedicate their lives to answering vital scientific questions impacting human health and the planet.”

Reporter Timothy Cama contributed.

Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2023. E&E News provides essential news for energy and environment professionals.

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe