Can libel suits be brought by a public figure?
Public figures have a more difficult time proving defamation. Politicians or celebrities are understood to take some risk in being before the public eye and many of them profit by their public persona. A celebrity must prove that the party defaming them knew the statements were false, made them with actual malice, or was negligent in saying or writing them. Proving these elements can be an uphill battle. However, an outrageously inaccurate statement that's harmful to one's career can be grounds for a successful defamation suit, even if the subject is famous. For example, some celebrities have won suits against tabloids for false statements regarding their ability to work, such as an inaccurate statement that the star had a drinking problem.
There are attorneys who specialize in defamation lawsuits. You can find a listing of specialists in your area at AttorneyPages.com.