Gertz v. Robert Welch, Inc.

http://en.wikipedia.org/wiki/Gertz_v._Robert_Welch,_Inc.

"Gertz v. Robert Welch, Inc., 418 U.S. 323 (1974),[1] was a case in which the Supreme Court of the United States established the standard of First Amendment protection against defamation claims brought by private individuals.

The Court held that, so long as they do not impose liability without fault, states are free to establish their own standards of liability for defamatory statements made about private individuals. However, the Court also ruled that if the state standard is lower than actual malice, the standard applying to public figures, then only actual damages may be awarded.

The consequence is that strict liability for defamation is unconstitutional in the United States; the plaintiff must be able to show that the defendant acted negligently or with an even higher level of mens rea. In many other common law countries, strict liability for defamation is still the rule."