Defamation is a false statement of fact, communicated to someone other than the person it is about, that damages that person's reputation. If the statement is written or otherwise fixed in a lasting form, it is libel. If it is spoken, it is slander. Truth is a complete defense, and pure opinion is not defamation at all, which is why most angry online arguments never become viable lawsuits.
Defamation is governed by state law, layered underneath a set of First Amendment rules the U.S. Supreme Court has imposed on all of it. That combination makes defamation one of the most misunderstood claims in American law. People assume any insult is actionable. Courts assume the opposite, and they dismiss weak cases early. Here is how the claim actually works.
What is the difference between libel and slander?
The distinction is about form, not severity. Libel covers statements fixed in a durable medium: newspaper articles, blog posts, social media posts, emails, reviews, photographs with captions, and broadcast content in most states. Slander covers spoken statements that evaporate when the conversation ends.
The difference used to matter enormously because slander plaintiffs generally had to prove special damages, meaning concrete economic loss, while libel plaintiffs often did not. That rule still exists in many states, but with an important carveout: slander per se. Certain categories of spoken accusations are considered so obviously harmful that damage is presumed. The traditional per se categories are accusing someone of a serious crime, saying they have a loathsome disease, attacking their fitness for their trade or profession, and imputing serious sexual misconduct. If a competitor tells your biggest client that you embezzle, that is slander per se in most states, and you do not need a spreadsheet of lost revenue to get past the pleading stage.
In the internet era, nearly everything that matters is libel. A post, a review, a group text, a comment thread: all fixed, all durable, all libel if the other elements are met.
What do you have to prove in a defamation case?
Every state phrases it slightly differently, but the core elements are consistent:
A false statement of fact. The statement must be capable of being proven true or false. "The contractor never pulled the permits" is a factual assertion. "The contractor is the worst in town" is opinion. Courts look at context: a one-star review full of hyperbole reads as opinion, while a specific factual accusation embedded in it can still be actionable. And falsity is measured by substantial truth. If the gist of the statement is accurate, minor errors in detail will not sustain a claim.
Publication. The statement must reach at least one person other than the plaintiff. Telling you to your face that you are a thief is not defamation. Telling your employer is.
Fault. This is where the First Amendment enters. Under New York Times v. Sullivan and the cases that followed, a public official or public figure must prove actual malice, meaning the defendant knew the statement was false or acted with reckless disregard for whether it was true. A private individual generally only has to prove negligence, meaning the defendant failed to use reasonable care in checking the facts. The gap between those standards decides many cases before trial.
Damages. Harm to reputation, which can include lost business, lost employment, emotional distress, and in per se cases, presumed damages. Some states also allow punitive damages where actual malice is shown.
Who counts as a public figure, and why does it matter?
Because the actual malice standard is so hard to satisfy, the public-figure question is often the whole ballgame. There are three rough categories. Public officials are people who hold government positions of authority. All-purpose public figures are people with pervasive fame, such as celebrities and national personalities. Limited-purpose public figures are ordinary people who have voluntarily injected themselves into a particular public controversy, such as an activist leading a rezoning fight. A limited-purpose public figure must prove actual malice only for statements related to that controversy.
Courts decide this question as a matter of law, and defendants push hard for a public-figure finding because reckless disregard is very difficult to prove. It requires evidence about the defendant's state of mind: that they entertained serious doubts about the truth and published anyway.
What defenses defeat a defamation claim?
Truth. A true statement is not defamation, no matter how damaging or mean-spirited. The burden of proving falsity generally sits with the plaintiff when the statement involves a matter of public concern.
Opinion. Statements that cannot be proven true or false are protected. So are statements of "rhetorical hyperbole" that no reasonable reader would take as literal fact.
Privilege. Some statements are absolutely privileged, meaning immune even if false and malicious. The most important is the litigation privilege: statements made in court filings and judicial proceedings. Legislators speaking in session enjoy a similar protection. Other statements carry a qualified privilege, such as an employer giving a job reference or a person reporting suspected crime to police, which is lost only if abused.
Anti-SLAPP statutes. A majority of states have laws targeting Strategic Lawsuits Against Public Participation. Where they apply, a defendant sued over speech on a public issue can force the plaintiff to show a probability of success at the very start of the case, and a plaintiff who fails typically pays the defendant's attorney fees. Anti-SLAPP motions have become the defining early battle of modern defamation litigation, and the strength of these statutes varies widely by state.
Retraction statutes. Many states require a plaintiff to demand a retraction before suing a media outlet, or limit damages when a timely correction runs.
How long do you have to sue for defamation?
The statute of limitations for defamation is short in most states, commonly one or two years from publication, and in a handful of states as long as three. Most states follow the single publication rule, which starts the clock when the statement is first published rather than restarting it every time someone reads the page. Republishing the statement in a materially new form can restart the clock. Because the window is short and the early motions are decisive, timing matters more in defamation than in almost any other civil claim.
What should you do if you have been defamed, or accused of it?
If you are the target, preserve the evidence immediately: screenshots with timestamps and URLs, archived copies, and the names of people who saw the statement. Reputational harm is easier to prove when you can document who received the statement and what changed afterward. A demand letter seeking retraction is often the first formal step, and in retraction-statute states it may be required.
If you are the one accused, do not quietly delete and hope. Deletion can look like spoliation once litigation is foreseeable, and it does not undo publication. Evaluate whether the statement was true, opinion, or privileged, and whether your state's anti-SLAPP law applies, because that can shift the economics of the entire dispute.
Either way, the merits turn on details: the exact words used, the audience, the state, and the plaintiff's public or private status. Small factual differences move these cases from strong to unfilable, which is why early, informed case evaluation is worth more here than in almost any other area of civil litigation.