Defamation
A false statement of fact that causes injury to someone's reputation, published to a third party.
Defamation is a false statement of fact, about an identifiable person, published to a third party, that causes reputational harm. Defamation in written form is libel; spoken defamation is slander.
The elements of common law defamation are: 1. A false statement of fact (not opinion) 2. About an identifiable person 3. Published (communicated) to at least one person other than the subject 4. With the required level of fault (actual malice for public figures; at least negligence for private figures) 5. That causes damages
Under New York Times v. Sullivan (1964), public officials and public figures must prove actual malice — knowledge of falsity or reckless disregard for truth — to recover. The heightened standard was designed to protect robust press coverage of public affairs.
Statements of pure opinion are not actionable — defamation requires a false statement of fact. 'I think Senator Smith is corrupt' is opinion; 'Senator Smith took a bribe' is a statement of fact that can be defamatory if false.
Defamation is one of the recognized categories of unprotected speech, meaning that defamatory statements can be punished without violating the First Amendment — but the First Amendment imposes significant constraints on the scope of defamation liability.