This is what makes it difficult, while First Amend offers no protection to make a statement containing claims, expressly stated or implied to be factual,  that may give an individual, business, product, group, government, religion, or nation a negative or inferior image (defamation), it protects the right for any individual, group or organisation to vilify and libel its views of an ideology, religion, government for the political and legal implications it advocates. It is the case for sharia law that belongs to the public and political debate.