The court... pointed to terminology such as “whitewashed,” “intellectually bogus,” “ringmaster of the [tree]-ring circus” and “cover-up” as “more than rhetorical hyperbole.”The linked article miscorrects the joke "tree-ring circus" to "three-ring circus." Here's the blog post that drove Mann to file a lawsuit — Mark Steyn calling attention to some football-and-hockey bad-taste humor.
There's "a line between rhetorical hyperbole and defamation."
Said the court that let the climate scientist Michael Mann — he of the "hockey stick" — to continue with his lawsuit against the National Review.