the law on slander
The common law origins of defamation lie in the torts of slander (harmful statement in a transient form, especially speech), each of which gives a common law right of action.
Defamation is a tort, however, and a person can sue someone if he or she suffers injury because of that person's defamatory statements. Defamation can be a tricky area of the law because there is a fine line between freedom of speech and the right of a person to protect his or her reputation.