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In the United States...a prosecution for blasphemy would violate the Constitution according to the 1952 Supreme Court case Joseph Burstyn, Inc v. Wilson.
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United States of America
Main article: Blasphemy law in the United States of America
A prosecution for blasphemy in the United States would fail as a violation of the U.S. Constitution. The First Amendment to the United States Constitution provides:
"Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press . . . ."
Because of the First Amendment's protection of free speech and religious exercise from federal interference, and the Supreme Court's extension of those protections against state regulation, the United States and its constituent state governments may not prosecute blasphemous speech or religious insults and may not allow civil actions on those grounds. In Joseph Burstyn, Inc. v. Wilson, the U.S. Supreme Court ruled that New York could not enforce a censorship law against filmmakers whose films contained "sacrilegious" content. The opinion of the Court, by Justice Clark, stated that:
"From the standpoint of freedom of speech and the press, it is enough to point out that the state has no legitimate interest in protecting any or all religions from views distasteful to them which is sufficient to justify prior restraints upon the expression of those views. It is not the business of government in our nation to suppress real or imagined attacks upon a particular religious doctrine, whether they appear in publications, speeches, or motion pictures." Blasphemy law - Wikipedia, the free encyclopedia