Libel About Protected Speech
Say you’re talking privately (not to the public at large) about someone, and say something that seriously damages their reputation. It’s an honest mistake on your part, and you aren’t animated by hostility towards the person; but the person learns about it and sues, claiming that the allegations were false and that you didn’t perform a reasonable investigation (i.e., were negligent).
In most states, including California, that could be actionable defamation, but is sometimes subject to so-called “qualified privileges.” They are privileges because they provide immunity from defamation liability (don’t confuse them with evidentiary privileges, which provide a right not to testify). They are qualified because they only apply so long as you made an honest and well-motivated mistake. They basically (to oversimplify slightly) raise the mental state the plaintiff needs to show from negligence as to falsehood to recklessness or knowledge.
Classic examples of qualified privileges include the “common interest” privilege, for instance when you’re talking to a business partner about an employee or a prospective contracting party, or when you’re talking to a fellow club member about a candidate for membership. They also include the “interest of another” privilege, for instance when someon
Article from Reason.com