As it pertains to journalism, this is what I found (all from the same article, link at the end):
What Is Libel?
Libel is published defamation of character, as opposed to spoken defamation of character, which is slander.
Libel:
- Exposes a person to hatred, shame, disgrace, contempt or ridicule.
- Injures a person’s reputation or causes the person to be shunned or avoided.
- Injures the person in his or her occupation.
Examples might include accusing someone of having committed a heinous crime, or of having a disease that might cause them to be shunned.
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- Privilege Accurate reports about official proceedings – anything from a murder trial to a city council meeting or a congressional hearing – cannot be libelous. This may seem like an odd defense, but imagine covering a murder trial without it. Conceivably, the reporter covering that trial could be sued for libel every time someone in the courtroom accused the defendant of murder.
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Public Officials vs. Private Individuals
In order to win a libel lawsuit, private individuals need only prove that an article about them was libelous and that it was published.
What Do You Need to Know About Libel and Libel Law?