Climate Scientist Wins $1M in 12-Year Defamation Lawsuit Against Conservative Journalists

By: Lauren | Published: Feb 16, 2024

In 1998, climate scientist Michael Mann published a graph projecting the planet’s possible warming patterns in the Nature journal.

That graph became wildly famous and sparked intense debate among the scientific community. Then, in 2012, a writer from the Competitive Enterprise Institute published an article comparing Mann to a convicted pedophile. And now, 12 years later, Mann has received $1 million as compensation for the slander.

Michael Mann’s “Hockey Stick” Graph

The complicated and very public story of scientist Michael Mann and his famous “hockey stick” graph,” has been going on for 26 years since he first published the graph in the Nature journal.

In blue is the original hockey stick of Mann, Bradley, and Hughes (1999 ) with its uncertainty range (light blue)

Source: Wikipedia

In the graph, Mann showed that planet Earth has been warming at a far more accelerated rate than ever before for the past 200 years, from the 1800s to the turn of the new millennium. And he believed that the rate was likely going to increase at a concerning rate in years to come.


Many Scientists Debated the Validity of the Graph

Soon after it was published in 1998, scientists from around the world began debating the validity of Mann’s graph. Some agreed with his data and projections, and others argued that he manipulated the data.

Photograph of climate scientist Michael Mann

Source: Wikipedia

It’s important to understand there are hardly any scientific theories that don’t ignite some kind of debate. And the idea that Mann’s graph was not 100% accurate is not what brought him to court 14 years later.

The Quote No One Could Stop Talking About

Instead, it was one quote from a writer named Rand Simberg that changed everything for Mann. Simberg wrote a blog post for the Competitive Enterprise Institute, a libertarian think tank, in which he compared Mann’s graph to the actions of Jerry Sandusky, a recently convicted pedophile.

Logo for the libertarian think tank company and publisher Competitive Enterprise Institute


Simberg wrote in his article, “Mann could be said to be the Jerry Sandusky of climate science, except for instead of molesting children, he has molested and tortured data.”

Who Was Jerry Sandusky?

In order to understand the magnitude of this comment, it’s crucial to know who Jerry Sandusky was and why this comparison was considered so aggressive.

Former Penn State assistant football coach Jerry Sandusky leaves the Centre County Courthouse after being sentenced in his child sex abuse case

Source: Patrick Smith/Getty Images

From 1969 to 1999, Jerry Sandusky worked as the assistant coach for the Pennsylvania State University football team. Then, in 2011, Sandusky was arrested and charged with the sexual abuse of 52 young boys while he was working as a coach. He was then found guilty on 45 of the charges and sentenced to 60 years in prison.

Another Writer Wrote against Mann in the National Review

Shortly after the article comparing Mann to Sandusky was released, another writer, Mark Steyn, published a different piece on the climate scientist in National Review.

Exterior of a building on the Penn State University campus

Source: Penn State

He wrote that Mann’s research was undoubtedly “fraudulent,” citing Mann’s emails to other scientists and members of staff at the university, which were leaked in 2009, as evidence.


Michael Mann Claims This Slanderous Article Changed His Life

After the two articles were published, Mann claimed that the authors were guilty not only of defamation but also of costing him money in regard to grant funding and other work-related income.

Exterior of the District of Columbia court of appeals

Source: @DCCourts/Facebook

So, he took his case to the Superior Court of the District of Columbia, and after a lengthy trial, the jury found that both Simberg and Steyn had made false claims or statements in their writing. And that Mann was eligible for financial compensation.


The DC Courts Gave Mann $1 Million

The judge and jury awarded Mann $1,000 from Simberg and $1 million from Steyn in punitive damages, stating that their writing had “maliciousness, spite, ill will, vengeance or deliberate intent to harm.”

Piles of US currency wrapped in black rubber bands

Source: Freepik

However, it seems that this trial is far from over, as both authors have announced they plan to appeal the ruling as soon as possible.


Mann Didn’t Have Sufficient Evidence of Loss of Income

Both defendants are appealing the punitive damages charge, claiming that Michael Mann did not provide sufficient evidence he lost any income due to their statements.

Lawyer explaining something to a person above an open book

Source: Freepik

In fact, they believe their controversial articles may actually have improved Michael Mann’s career, as he quickly became one of the most famous climate scientists in the world, thanks to the disputation.


The Case Focused Solely on Defamation, Not Climate Change Data

The judge for the case, Alfred Irving, made a statement explaining to the public that this case was solely based on the question of whether or not Mann was defamed in print, not if his data was correct or not.

A judge's gavel sits on a wooden table

Source: Freepik

Irving said his job was not to determine “whether there’s global warming”  but instead to determine if these statements did cause Mann financial hardship.


The Climate Debate Is More Important Than Ever Before

Today, more than 25 years after Michael Mann released his “hockey stick” graph, the world is still debating the planet’s climate change problem. And while the majority of people now agree the world is facing imminent warming and consequent problems, others argue that science is still being manipulated to prove a point.

Climate activist protest participant holds a sign that reads, “We still have a choice”

Source: Michel Porro/Getty Images

But as Kate Cell, a member of the Union of Concerned Scientists, explained, this case will likely make “people think twice before they lie and defame scientists.”


What’s Next for Michael Mann?

While the defendants plan to appeal the court’s decision regarding the punitive damages to be paid to Mann, he has an appeal of his own to focus on.

Scientist Michael Mann attends the New York screening of the HBO Documentary "How To Let Go Of The World And All The Things Climate Can't Change" on June 21, 2016 in New York City

Source: Slaven Vlasic/Getty Images

In 2021, the DC Superior Court ruled that neither of the publications who released the articles in question were liable for defamation, but Mann is appealing that decision now. He said in a statement, “We think it was wrongly decided. They’re next.”