Statement Person Reputation Harming Professional Court Defamation True

In the United States, people can "sue" (take to court and ask to be paid money) for defamation, "claiming" (saying that something is true) that the "defendant" (the person who is brought to court and accused of a crime) "knowingly" (with full awareness and knowledge) lied about a person or business in order to harm the reputation of that person or business. Proving that a statement was "false" (not true) is pretty "straightforward" (direct; simple; easy), but a false statement is defamation only if the person who made that statement did it while knowing that it was false.

Defendants can defend themselves against defamation by arguing that they had a "good-faith belief" in the statement, meaning that they honestly thought the thing they were saying was true. In these cases, the defendant will have to "prove" (show evidence of) what information was available to him or her at the time when the statement was made and show that it was "reasonable" (rational; logical) for him or her to have believed it was true.

Defendants can also defend themselves by arguing that the statement was merely their personal "opinion" (what one thinks). It is not illegal to share one's opinion - in fact, it is protected under "free speech" (freedom from being punished for what one believes or says). In these cases, the defendant must prove that what he or she said was "presented" (shared with others) as a personal opinion and not as a "statement of fact" (something that is 100% true).

There are other defenses against claims of defamation, but the two described above are the most common and best known.