The next time you want to blast someone with a sharp-tongued Facebook status update or on Twitter, you might want to tone it down a bit or delete it altogether.

While the laws regarding defamation and libel are not entirely settled as to how they apply to the fast-emerging world of social networking sites, the consensus so far is that statements made on sites like Facebook, Twitter, and MySpace media can be defamatory.

As long as the traditional elements of the tort of defamation are proven by the injured party, the person who wrote the injurious words may be hauled into court and held responsible. That means you may have to pay big time for using your 140 characters or less on Twitter to injure the reputation of another party.

In the most recent cases, a frustrated apartment tenant who complained to her handful of Twitter followers that her apartment manager allowed mold to grow in her apartment was sued for defamation by the manager. In another case, an English man was awarded financial damages after a former classmate posted on Facebook, claiming the man was homosexual.

Both of those cases and dozens more like them filed in courts all over the United States show how defamation and libel law is once again being forced to keep up with evolving technology, much like what happened with the invention of email and text messaging years ago.

The common law tort of defamation is a false and malicious published statement that damages somebody's reputation. Libel is the form of defamation which includes written statements, pictures, and any other representations such as cartoons.

The party making a defamation claim (the plaintiff) must ordinarily prove four elements:

1) a publication to one other than the person defamed;

2) a false statement of fact;

3) that is understood as

a. being of and concerning the plaintiff; and

b. tending to harm the reputation of plaintiff.

If the plaintiff is a public figure, he or she must also prove actual malice in order to prevail in court on a defamation claim.

While many people use the terms interchangeably, libel and slander are not one in the same. Libel is a defamatory statement that is written or contained in images, while slander is defamation that is spoken. In some cases, such as with television or radio broadcasters who read from written scripts, the harmful statement may be both libel (written) and slander (spoken).

Also, if you’re thinking about re-tweeting a defamatory tweet posted by another or party or copying a defamatory Facebook update or wall post, you better think again. Just like with traditional libel and defamation, republications of the injurious words online are considered actionable, too, with some exceptions provided for legitimate news agencies and internet service providers.

So, while it may be tempting to call someone out on Facebook or on Twitter, the potential legal consequences of defamation that could result mean it’s probably not a good idea.