The Washington, D.C. Superior Court’s May 22, 2025 ruling against Michael Mann is the latest in a series of defeats for the climate scientist’s prolonged legal offensive against his critics. Judge Alfred S. Irving ordered Mann to pay $477,350.80 in attorney’s fees and related costs to the Competitive Enterprise Institute (CEI) and Rand Simberg, following their successful partial dismissal of claims under the District’s Anti-SLAPP Act.

This judgment comes just months after a separate ruling ordered Mann to pay $540,820.21 to National Review. Together, the two awards raise Mann’s current liability to over $1.1 million—a staggering total for a campaign that began over a decade ago with the aim of silencing dissent through strategic litigation.

Mann’s lawsuit, filed in 2012, named CEI, Simberg, National Review, and Mark Steyn as defendants over criticism of his scientific work, specifically the “hockey stick” graph that catapulted him to fame in climate policy circles. From the beginning, Mann positioned the suit as a defense of science against ideological attack. The courts have increasingly seen it otherwise.