But it is the third approach that could be most consequential for Americans. It’s known as “libel tourism” and here’s how it works: A book published in the United States names an individual abroad who supports terrorist groups. That individual — for the sake of discussion, let’s say he’s a Saudi petro-billionaire with a home in London — goes online and orders a few copies, which arrive in the mail. He takes those books to a British attorney who files a lawsuit complaining that his client has been libeled. The billionaire knows it will be much easier to prevail in the United Kingdom than it would be in an American court, where the First Amendment and decades of case law provide free speech protections. (Under English law, by contrast, the burden in a libel case is on the defendant to prove his innocence — which can be impossible if he’s been using confidential sources or even just sources who don’t want to cross an ocean and take part in a courtroom battle.)

http://muslimsagainstsharia.blogspot.com/2008/09/islamists-attacking-freedom-of-speech.html