Defamation is a false statement of fact, published to a third party, causing reputational harm.
Fault. Private figures on matters of private concern must generally show negligence. Public officials and public figures must show actual malice — knowledge of falsity or reckless disregard for the truth, proved with convincing clarity.
Limited purpose public figures are those who have voluntarily entered a public controversy, and businesses that have publicised themselves on a disputed issue may qualify.
Fact versus opinion. Statements that cannot be proved true or false are not actionable; statements of opinion implying undisclosed defamatory facts are. Context and the audience’s expectations matter.
Substantial truth is a complete defence.
Privileges. Absolute for statements in judicial proceedings and legislative debate; qualified for communications on a subject of common interest, lost by malice or excessive publication.
Damages. Presumed for statements defamatory per se in some jurisdictions — imputing criminal conduct, a loathsome disease, professional incompetence, or serious sexual misconduct. Otherwise special damages must be proved.
Single publication rule treats one edition as one publication, with the limitation period running from first publication rather than from each view.
Retraction statutes limit damages where a timely retraction is demanded and published.