<P> The origins of the United States' defamation laws pre-date the American Revolution; one influential case in 1734 involved John Peter Zenger and established precedent that "The Truth" is an absolute defense against charges of libel . (Previous English defamation law had not provided this guarantee .) Though the First Amendment of the U.S. Constitution was designed to protect freedom of the press, for most of the history of the United States, the U.S. Supreme Court failed to use it to rule on libel cases . This left libel laws, based upon the traditional "Common Law" of defamation inherited from the English legal system, mixed across the states . The 1964 case New York Times Co. v. Sullivan, however, radically changed the nature of libel law in the United States by establishing that public officials could win a suit for libel only when they could prove the media outlet in question knew either that the information was wholly and patently false or that it was published "with reckless disregard of whether it was false or not". Later Supreme Court cases barred strict liability for libel and forbid libel claims for statements that are so ridiculous as to be patently false . Recent cases have added precedent on defamation law and the Internet . </P> <P> The First Amendment guarantees of Freedom of Speech and Freedom of the Press provide defendants in the United States significantly more protection than the countries of the Commonwealth and Europe . Some variation exists among the several states to the extent the state's legislature has passed statutes or its courts have handed down decisions affecting the contours inherited from the common law . Some states codify what constitutes slander and libel together into the same set of laws . </P>

Why do we have defamation laws in this country
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