All states except Arizona, Arkansas, Mississippi, Missouri, and Tennessee recognize that some categories of statements are considered to be defamatory per se, such that people making a defamation claim for these statements do not need to prove that the statement was defamatory. In the common law tradition, damages for such statements are presumed and do not have to be proven. Traditionally, these per se defamatory statements include:
- Allegations or imputations of criminal activity (sometimes only crimes of moral turpitude)
Under United States law, libel generally requires five key elements. The plaintiff must prove that the information was published, the defendant was directly or indirectly identified, the remarks were defamatory towards the plaintiff's reputation, the published information is false, and that the defendant is at fault.
In November of 2006 the California Supreme Court ruled that 47 USC § 230(c)(1) does not permit web sites to be sued for libel that was written by other parties