Substantial truth

Substantial truth is a legal doctrine affecting libel and slander laws in common law jurisdictions such as the United States or the United Kingdom.

Under the United States law, a statement cannot be held to be actionable as slanderous or libelous if the statement is true; the substantial truth doctrine extends this protection by holding that a statement with "slight inaccuracies of expression" do not make the alleged libel false.

This doctrine is applied in matters in which truth is used as an absolute defense to a defamation claim brought against a public figure, but only false statements made with "actual malice" are subject to sanctions. A defendant using truth as a defense in a defamation case is not required to justify every word of the alleged defamatory statements. It is sufficient to prove that "the substance, the gist, the sting, of the matter is true."

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