Here are the some exceptions to defamation –
Truth for public good – Truth is an absolute defense in civil cases. But, in criminal proceedings, it must be proved that the imputation was made for public good. Notwithstanding the intention of an individual, no defamation suit holds good against him if he imputes something true. Accusations, censure or imputation made in good faith by person having lawful authority are also exceptions.
Fair comment – Exception of fair comment is allowed in case it is made clear that the publication clearly expresses an opinion and does not support any facts. Similarly expression of an opinion in good faith regarding the merits of an individual’s performance thrown open to the public for a judgment is a fair defense for a person charged with libel.
Defamation is a false and unprivileged statement of fact that is harmful to someone’s reputation, and published “with fault,” meaning as a result of negligence or malice. State laws often define defamation in specific ways. Libel is a written defamation; slander is a spoken defamation.