Do we like Michael E. Mann?
Our score: 7 out of 10. A long, steady record of defending climate science and no harmful words found, with one real stain from his famous trial.
Michael Mann is the climate scientist behind the 1999 'hockey stick' graph, a reconstruction of Earth's temperature over the past thousand years. He is now a professor at the University of Pennsylvania and has written a string of books, the latest being Our Fragile Moment. The graph made him a target for climate deniers for more than two decades, which explains most of what followed. We couldn't find a fully sourced early-life story, so that's the honest limit of the backstory.
The big scandal is his defamation case against bloggers Mark Steyn and Rand Simberg, who attacked his work in 2012 posts. In February 2024 a D.C. jury gave him $1 in nominal damages from each, plus $1 million in punitive damages against Steyn and $1,000 against Simberg. His lawyer said National Review and the Competitive Enterprise Institute, dismissed earlier, were 'next'. It looked like a clean win for the climate side.
Then it got messy. Judge Alfred Irving cut the punitive award against Steyn to $5,000, calling it grossly excessive, and ordered Mann to pay over $530,000 in National Review's legal fees under D.C.'s anti-SLAPP law. He also found that Mann's lawyers presented a wrong grant-funding figure at trial. Mann's side says the error was corrected before trial and that nobody meant to deceive the jury.
In January 2026 the judge reaffirmed that sanctions order. The court said the exhibit showed about $9.7 million in lost grant funding when the correct figure was $112,000, and that Mann and his lawyers 'acted in bad faith'. He was ordered to pay Steyn $11,400 and Simberg $16,700. National Review later waived its fee claim in a settlement, and whether the Steyn and Simberg appeals go ahead is still unclear.
On the harm test, we found nothing nasty. His public work is arguing that climate action is still possible, and he says the obstacles are 'entirely political' rather than technical. He pushes back on doom-mongering as unjustified by the science. We found no statements from him on trans people either way, and no sign he works with people who push harm, so that's a clean pass on what we could see.
The good stuff is his long public role defending climate science against sustained attacks, and teaching and speaking to students. Many honours, including the Humanist of the Year award and election to the National Academy of Sciences, appear on his own listings, but we couldn't open a dated news source for them. Fair to say he has wanted to be the loud voice for the planet and has paid for it.